Arrowmail - Email services for today's business

on this Page:

  (far right) "Is this what you mean by Push Email?"

Smarthost\SMTP Server

Ring Fence Package
A combination of all our services to keep your company's email system safe and reliable

Lost Email Protection
Mail-Server &
MX Records

High Accuracy Spam Filtering

Anti-Virus Email Filtering

What our customers
have to say:

Testimonial from Supremia International PLC

"Our Exchange server was being hit with 1000s of spam emails a day.
When we routed our email via Arrowmail's servers it all went quiet,
the server and Broadband connection were faster and the level of spam in users' Inboxes was dramatically reduced."


Support Services for Existing Company Email Systems


Could your company's mail-server do with some help in today's challenging email environment?


A partnership between your mail-server and our
highly-available, versatile mail-servers, directly connected to the Internet's fast lane, provides the most cost-effective, complete business email solution.


Achieve the perfect email system for your business without having to upgrade your in-house system or relinquish too much control.

Free 2 month trial for companies and organisations - Click Here


Arrowmail's SMTP Servers can:-

Get your business emails delivered reliably

Send large quantities of emails quickly

Enable your website to email visitor feedback to you

What makes
our Smarthost
so smart?

Smarthost - An SMTP Server for Expert Email Delivery

Why Can't your own Server send out Emails Reliably Anymore?

As spam now makes up 95% of all email traffic, companies and ISPs are taking strong measures to reduce the amount of spam their users receive, which makes it harder to get genuine emails delivered to recipients who want to receive them.

For a mail-server to successfully send out emails it has to have the proper credentials and be trusted by the rest of the mail-servers on the Internet.
If your mail-server can't get emails delivered to Hotmail, Yahoo and AOL addresses,
amongst others, then it may not be trusted, probably because of a DNS name configuration problem or the IP address it's operating behind is on someone's blacklist.

Maintaining the trustworthiness of your sending server is an on-going job.
This involves keeping up with the latest "good behaviour" standards, being fully
RFC-compliant, staying off blacklists and requesting ISPs to trust your server.
We do all of this, and more, to keep our sending servers trusted and constantly monitor them for problems.
We have multiple IP address ranges, a server in the US and backup routes with partner
mail-servers, just in case we have difficulties getting emails delivered to certain addresses.

You can have your company's mail-server pass all of it's outgoing emails directly to our servers which will then do the actual sending. That's called "using a Smarthost".


Smarthost service:

(More details...)

What Emails can I send using your Smarthost?

Anything that's not spam or contains a virus.
You can put any email address you like as the From and Reply-To fields in the emails you send using our servers.

How Many Emails can I Send with your Smarthost?

We estimate that an average business user sends between 300 and 500 emails per month.
A company may send out a newsletter to, say, 1000 customers and perhaps a few people forward all their incoming email to their Blackberry.
A typical company with less than 20 employees might send out 5000 emails per month for which we charge £14.50.
If you go over the 5000 mark in some months, even by as much as 50%, we're not going to worry. There's no "hard limit" to the number of emails you can send and we'll certainly talk to you first, before taking any action, if you regularly exceed your allocation by a large amount.
For every extra block of 5000 emails you want to send, we charge £7.50 per month, up to 50,000, after which it drops to £7.50 per 10,000.

There's no real limit to the amount of emails we can send so, if you're a large company or ISP, tell us what you need.
If you're not sure how many emails you're going to send, don't worry, we'll be counting them during your free trial period, to see which price-band you fit into.

We don't charge by the size of the emails you send.
A one line email costs the same as an email with a 10mb attachment and there's no monthly limit to the total amount of bandwidth you can use to send all of your emails.

An email sent to multiple recipients splits into one email per recipient at our servers.
So, for example, an email with a total of 50 To, CC and Bcc recipients counts as you sending 50 emails.

What Size of Email Attachment can I send using your Smarthost?

We accept email attachments up to 40mb in size but this does not guarantee that the receiving server will accept attachments of this size and, in general, you'll be lucky if you can successfully send a file larger than 10mb.
We just don't want our servers to be the limiting factor.

What Types of Files can I send as Attachments?

All except those likely to contain a virus.
EXE files are the only file-type we block that's likely to cause you a problem, but the majority of email systems block these as well.
If you ever need to send an EXE file, you can rename the file extension to TXT and instruct the recipient to rename it back when they've received it.
A full list of the files we block is given in the anti-virus section later on this page.
We don't block password-protected files but you should be aware that some email-systems do block them on the basis that they can't be scanned for viruses.
Using one of the many cloud storage services that are now available with several free gigabytes is probably the best way to send large files or file-types likely to be blocked.
After dragging the file you want to send to the "cloud folder" on your computer it will then be uploaded to the Internet and you can then just send a link to the file in your email.

Auto-Correction of Misspelled Email Addresses

It's very easy to make a typing error when entering an email address.
If the error is in the domain part of the address (to the right of the @ symbol) then the error will most likely create a recipient domain that doesn't exist and so you will get a failure message back from our servers, you will then have to realise your error and resend the email to the correct address.
There are many common misspellings of domains that occur regularly:-
entering instead of is one example.
When the correct spelling is obvious and unmistakable, like in the above, our servers correct the error and send the email to the corrected address.
You also get an email letting you know that your email has been auto-corrected:-


This is an automated response from the Arrowmail email system.

You just sent an email to which is not a valid email domain but is a common miss-spelling for

We have corrected the domain part of the address to and are attempting to deliver the email.
You DO NOT need to resend this email but you may want to correct this address in your contacts list.

Arrowmail Support

Our servers do make an attempt to send the email to the original address that you entered before attempting to correct it, in case it wasn't a mistake after all.

To Authenticate or not to Authenticate

When you want to send an email to our Smarthosts you usually have to provide the username and password we've given you, before your email is accepted.
Many mail-servers, such as Exchange, can perform this authentication automatically but there are some situations where authentication by the sender is not possible.
If you tell us the IP address your mail-server is operating from, we can exempt this IP address from having to authenticate before sending.
The only problem with this is, if you change your IP address, you'll have to remember to let us know the new IP address in order to continue to send emails without authentication.

Using our Smarthosts to send out Newsletters and Marketing Emails

Arrowmail is about sending standard business and personal emails as reliably as possible.
We'd rather not send Marketing Emails, as it's this type of email that causes us all the problems with complaints about us sending out spam.
Saying that, we also have many customers who send Newsletter/Marketing emails through us successfully and without any problems.
The question is, do you know the ground rules for sending these types of emails?
Will you stick to them despite the temptations to market your product or organisation as widely and forcefully as possible?
Are you prepared to put in the effort to keep your mailing lists up-to-date?

If your main purpose in considering using Arrowmail's smarthost service is to send out Marketing emails then please read our rules on this page before wasting your time and ours by applying for a trial, generating complaints for sending spam, getting our servers blacklisted and having your account suspended.

Who Are Ya? Who Are Ya?

We get a lot of fraudsters applying for a free trial of our Smarthosts, hoping to use them to send out their spam so, when you apply please help us to confirm that you are genuine by:-

1 -

Using your company email address and not a free address such as Yahoo or Gmail.

2 -

Giving us the address of your company website.

3 -

There may be perfectly valid reasons why you can't do any of the above so email your request to or call us so you can explain your situation.

We value our customers and apologise for any delay or inconvenience our security checks may cause.

What Happens if Your ISP is Blocking Port 25?

To send email on the Internet you must use TCP Port 25.
Some ISPs block this port, outgoing, to prevent virus programs with built-in
mail-servers, sending out spam and other undesirable emails from an infected PC.
The only thing you're allowed to connect to, over port 25, is the ISP's own SMTP server which you are, therefore, required to use.
Using the ISPs SMTP server may be fine but sometimes, if you aren't using a From address in your outgoing emails that has been allocated to you by the ISP, these emails will be rejected by this SMTP server.
The solution is to send your emails to our Smarthost using a different TCP Port and we'll then send these emails on to their destinations using the standard port 25.
All our servers are setup to receive emails over ports 25 and 587.

There are Emails that our Smarthost Just Can't Deliver

Here's a contribution from our Smarthost Administrator:-

(Show all of this article...)


"It's my job to monitor the mail queues on Arrowmail's Smarthost Servers to check that things are running smoothly, and the queues I'm particularly interested in are the Outgoing Queue, the Retry Queue and the Bad Queue.

The vast majority of emails zip in and out of the Outgoing Queue in a fraction of a second, on the way to their destination.

If the first attempt to send an email fails then this email stays in the Outgoing Queue for an hour and, every minute, another attempt is made to send the email to each of the servers listed in the destination's MX records, in turn and in order of priority.

An attempt is even made to send to the default IP address of the recipient's domain as the RFC documents that specify how email should work, don't actually require the use of MX records.

Emails often hang around in the Outgoing Queue for 10 minutes or so because the receiving mail-server is playing the "grey-listing" game: purposely refusing an email for a set period of time to test the persistence of the sending server, with the assumption that
mail-servers sending millions of spam emails won't be very persistent.
You've never seen servers as persistent as our Smarthosts!

Other emails don't get delivered because there are no DNS records containing instructions on where to deliver them, or the mail-servers that are specified aren't responding.
There are 4 main reasons of this:-

1 -

The To: email address is spelled incorrectly.
An email to johnsmith28@hotmail.comn is never going to be delivered because the
top-level domain is invalid, but Outlook doesn't complain about this when you click Send.

2 -

The email trying to be delivered is an automated reply to some spam that's been received from a made-up email address.
This could be an Out-of-Office reply, a polite message saying that the email to, or some equally unlikely sounding member of staff you've never had, couldn't be delivered, or even a message from your server saying:-
"Your last email was rejected as spam".

Please, all you Exchange Administrators out there, these messages, provoked by a spam email, are just as much a waste of Internet bandwidth as the spam itself, so stop your server generating them!
Instructions on how to stop Exchange doing this are here.
Or perhaps you just need a better anti-spam system, like the one found elsewhere on this page.

3 -

The To: email address, or even the whole domain itself, was once valid but has now lapsed and the person or company you're trying to contact has either got a new email address or ceased to exist.

4 -

The recipient's mail-server is having temporary technical problems or perhaps the MX records are in the process of being changed.

When an email still can't be delivered after an hour, 2 things happen:-

1 -

The email moves to the Retry Queue.

2 -

A warning email is generated and sent back to the sender which says:-


Email Delivery Status Notification from

We've been trying to send the attached email message every minute
for the last hour without success.
The email has now been moved to the Retry Queue where further attempts to send it will be made once an hour for the next 3 days.
If the message can't be delivered after 3 days you will be sent another
notification email.

Only a small percentage of emails in the Retry Queue ever get delivered
and this is usually because the recipient's email address is invalid,
either it's spelled wrongly or is no longer current.
Please check this now and, if you find an error, send a new email with the
correct address information.

This warning email also contains an extract of the conversation between our Smarthost and the receiving mail-server which often reveals the nature of the problem: non-existent user, mailbox full, etc.

This warning email is sent because you need to know if your email hasn't been delivered after and hour and, most-times, you'll spot the spelling mistake that you made in the To: or CC: address straight away, correct it and re-send the email.

An attempt to deliver emails waiting in the Retry Queue is made once every hour for
three days.
This gives time for any failed server to be repaired or changed MX records to propagate around the Internet.
To be honest, only a very small percentage of emails, usually those destined for servers that manage to recover from their technical difficulties, ever get off the "Death Row" of the
Retry Queue, and that's despite all the conscientious efforts of our Smarthosts.

The Retry Queue is a great indicator, for me, as to when there are problems I need to investigate.
For example, if the Retry Queue suddenly has 200 emails waiting to go to addresses, I have to activate a routing rule to send emails, destined for Yahoo, via a one of our alternative mail-servers while I approach Yahoo to see what they think we've done wrong.

After 3 days is up, emails from the Retry Queue move to the Bad Queue and the sender receives this obituary:-


Email Delivery Status Notification from

The attached email could not be delivered and has now been deleted
from our servers.

Either the recipient's mail-server refused to accept the email or
the email has been in our Retry Queue, trying to be delivered for the
last 3 days without success.


Sometimes you'll receive the above message just minutes after sending an email if the receiving server flatly refuses to accept the email.
When a server refuses an email with an error-code in the 500s, RFC-compliance means we mustn't attempt to send that email again.

Emails in the Bad Queue are periodically deleted.

It's worth mentioning that if you send an email to multiple recipients, including copies (CCs) or blind copies (BCCs), your email splits into one email per recipient when it arrives at our Smarthosts and each email is then treated separately, so one bad address won't prevent your email being delivered to all the other recipients.

Encrypting Outgoing Emails

Our Smarthost supports (but doesn't require) TLS encryption (Transport Layer Security) when receiving emails from your server.
Using TLS means your emails will be strongly encrypted as far as our servers.
To enable this on your Exchange Server is simply a tick in a box (exactly where to find this tick-box is shown on our Smarthost configuration instructions page here).

Whether or not you use encryption to send emails to us, our Smarthosts will attempt to negotiate an encrypted channel when sending your emails onto the receiving mail-server but, in most cases, this is declined by the other mail-server and the emails pass in plain text.
Our Smarthosts do their best to keep your outgoing emails encrypted but can't guarantee they'll remain encrypted all the way from your Outbox to the recipient's Inbox.

Create a Special DNS Record to Help us Send your Emails More Reliably

If you decide to use our Smarthost servers, you can help lessen the chances of your emails being classified as spam by creating a special DNS record called an SPF record

This DNS record is to comply with the Sender Policy Framework (SPF) anti-spam initiative and it identifies our servers as being approved for sending emails from your domain.

For more details about how to create an SPF record, click here.

We also attach a DKIM signature to each outgoing email to comply with another anti-spam initiative.

Smarthost Prices

Monthly Charge

Emails Sent per Month





















each additional 5000, up to 50,000

add £7.25


each additional 10,000 over 50,000

add £7.25


Email, call 0800 634 9870 or fill out this webform for a free
1 month trial.

Smarthost Standby Service

So you're mail-server's sending out emails just fine at the moment, but wouldn't you like some insurance in case it's suddenly blacklisted by one or more large ISPs?
We can give you access to our smarthosts, either by username and password or by anonymous access from your specific IP addresses, so that you can, at any time, divert all your outgoing email, or just certain addresses, via our smarthosts.

This standby service costs £2.95/month which allows you to send up to 1000 emails for testing, maintenance, minor problems etc.
When you need to send more, we'll just invoice you monthly for the extra emails at our standard rate.

^ Top of Page ^


Ring Fence Your Mail-Server

What we mean by this is to throw a protective "wall" around your server in order to keep it
safe from all the "nasties" out there on the Internet and make sure your outgoing emails get delivered reliably.

It's actually a combination of 4 of our services, detailed elsewhere on this page:-
Spam Filter
Lost Email Protection


Ring Fence your server:

(More details...)

Our Ring Fence service requires no equipment or software to be installed on your server or your LAN.

These 2 steps are required to set it up:-

1 -

Edit the DNS MX records for your email domain.
You need to set our mail-servers to be the ones responsible for all emails sent to your domain.
You do this by editing the DNS MX records for your domain as shown below:-

Setting up these 3 MX records for your domain will make your email come to our servers


We're happy to edit your DNS settings for you if you can let us know your domain registrar control-panel logon details.
After changing your MX records, all incoming emails sent to your domain will now come to our servers.

This has the added bonus of reducing the amount of Internet bandwidth and server resources you're wasting on dealing with spam.

2 -

Configure your mail-server to use our servers to send all your outgoing email.
If your mail-server is Microsoft Exchange, there are instructions for configuring it to send all outgoing email using our servers here.
We're happy to perform these configuration steps for you if you're prepared to give us remote access to your server.

Lost Email Protection

If your server or Internet connection fails, we'll hold all your incoming email on our servers, indefinitely, until your server comes back on line when they'll then be automatically forwarded on.
While your server is off-line we can send a copy of all incoming emails to an external address, such a Gmail, so you can continue read incoming emails.
You can have up to 4 email domains covered by Lost Email Protection in our Ring Fence package.


We scan all attachments in your emails for viruses and delete them if any are found.
Attachments of types used almost exclusively for sending viruses are also removed.

Spam Filtering

We classify all your incoming emails into:-

Not Spam

These are passed, unchanged onto your server.

Definite Spam

These are deleted.

Probable Spam

These have their Subject Line modified to add the Spam Score so that you can use Outlook Mailbox Rules to automatically move these emails, as they come in, to your Junk E-mail folder where you can check them, occasionally, for False Positives.

Optionally, we can send all Probable Spam to a single separate mailbox on your server so that one person at your organisation can check for False Positives for all of your users.

Spam that our servers have missed, or any False Positives you find, can be re-submitted to our Spam Filtering system. Instructions on how to do this are here.
Phishing and Backscatter emails are also trapped by our Spam Filter.


All your outgoing emails are sent from your server to our SMTP servers which then deliver them to their final destinations.
Sending emails used to be a simple process but, with all the anti-spam measures now in place across the Internet, it requires special techniques and configuration settings to maintain a
mail-server's status of being trusted by other mail-servers as a source of genuine emails.


Our Ring Fencing Package costs from £5.95/month. Full pricing details here.
Email, call 0800 634 9870 or fill out this webform for a free 1 month trial.

^ Top of Page ^


These 4 services,
combined with a
Exchange server, are all you
need for a
business email system

Lost Email Protection

What will happen if your in-house mail-server or Internet connection stops working?
How much of an impact will the lack of access to your email have on your business?

If you don't have any backup mail-servers in place, when your primary system fails there will be no way to access you company email, as it will be sat in the retry queues of many different mail-servers, all over the Internet and, after an hour or so, people who've sent you emails will start to receive "Mail Undeliverable" messages, which is not good for the reputation of your business!

To overcome this problem, you can edit the MX records for your email domain to set our mail-servers to be additional, lower-priority servers responsible for receiving emails destined for your domain.
This means that, in normal operation, all your emails will continue to go straight to your server but, if your server is off-line, your email will, instead, automatically come to our servers.
We'll then hold on to your incoming email, indefinitely, until your server comes back on line when they'll be automatically forwarded-on to your server. Additionally we can send a copy of the waiting emails to an external address you nominate, such as Gmail.


Lost Email Protection service:

(More details...)

If your company runs its own email system using a server located at your main office then you're likely to have only a single MX record, such as shown below:-

An example of a single MX record for an email domain

If this server becomes unavailable there's nowhere for your emails to be delivered!

You can add our 3 servers as lower priority MX records, as shown below:-

An example of a main MX record and 3 backup MX records

When a mail-server is delivering an email, it first tries to send it to the nominated receiving server with the highest priority and, if this fails, tries the server with the next-highest priority and so on.
Priority, or preference, is a number between 0 and 99 and the lower the number, the higher the priority.
It would be extremely unlikely that all 4 servers, in the above example, are unavailable at the same time.

With your MX records setup as above, if your server or Internet connection ever has a problem, our servers will be receiving your emails and attempting to forward them on to your server every 15 minutes, indefinitely, until your server comes back on-line.

We can also send a copy of all the emails waiting on our backup servers to an external email address that you nominate, such as a Gmail address, where you can then read the emails that have been sent to you while your server's down.
When your server comes back on-line, all the originals of these emails will still be delivered to your users' mailboxes.
The only catch with this is that, in the external mailbox, all your company's emails are lumped together so, whoever is checking it, can read everyone's emails. You'll therefore have to decide if you want this feature and who it's appropriate to allow to access this external mailbox.
You also have access to our WebSend webpage which allows you send emails that appear to originate from your normal company email address. Have a look at this page here.
With forwarding to an external address and the WebSend page you can almost operate as normal when your email system has failed.

When your server is operating normally, the occasional email will get sent to our backup servers. These will be immediately sent on to your server without generating a copy to the external address.

We're happy to create the appropriate MX records for you if you can give us access to your DNS control panel.


Lost Email Protection costs £3.75/month for the first email domain and £1.49/month for any additional domains you may have.
Email, call 0800 634 9870 or fill out this webform for a free 1 month trial.

^ Top of Page ^


Get Arrowmail's servers to automatically
collect, store and forward your company's email if your system ever fails

High Accuracy Spam Filtering

1,000,000,000 Spam Emails not Served

Telling the difference between spam and genuine email, a task so easy for a human, is the hardest job our mail-servers have to perform.

Our priority is always to minimise the number of false positives - genuine emails labelled as spam - and to do this we employ a combination of all the latest spam detection techniques.
This allows us to eliminate over 98% of spam while miss-classifying as spam only a tiny percentage of genuine emails.

I doubt you'll find a better system.


Spam Filtering service:

(More details...)

This does mean the odd spam message will make it into your Inbox (some days are worse than others) but, more importantly, some genuine emails will need rescuing from your Junk folder, a job only a human can do.

To take advantage of our anti-spam system you'll need to modify the MX records for your email domain so that all incoming emails are routed via our servers before being send on to your server.
Your MX records should be set as shown below, substituting your email domain for

Setting up these 3 MX records for your domain will make your emails come to our servers

There's more information on MX records here.
We're happy to create the appropriate MX records for you if you can give us access to your DNS control panel.

Classifying Emails into Various Categories

We then classify all incoming emails into 3 categories:-

Not Spam

These are passed on, unchanged, to your server.

Definite Spam

These are deleted.

Probable Spam

These have their Subject Lines modified to add the Spam Score, as shown below, so that you can use Outlook Mailbox Rules to automatically move these emails, as they come in, to your Junk E-mail folder which you can then check, occasionally, for False Positives.

3 examples of modified Subject Lines are shown below:-

Spam emails showing the Spam Score modification we make to the Subject line

The characters your rule should look for in the Subject Line are:-
[***SPAM*** Score/Req:

Optionally, we can send all Probable Spam to a single, separate mailbox, on your server or ours, where one person at your organisation can check for False Positives for all your users.

If you take the option for all your company's Probable Spam to go into one mailbox on our servers, each email stays there for 7 days before being automatically deleted.
This gives a chance for someone in your company - the Spam Meister - to use, most likely, Outlook Express and an IMAP account to check the Spam folder for false positives - doing this once a day is usually sufficient.

If you find false positives from regular correspondents then you can send us their email addresses for white-listing.

You can forward any spam that makes it into your user's Inboxes, as well as any False Positives you find, back to us, so our spam filtering system can learn from it's mistakes.
They have to be forwarded in a special way in order to preserve their original formatting, details are here.

Refusing to Accept Emails from Blacklisted Servers

95% of spam never makes it to our Spam Filtering system because the servers trying to send them to us are on a blacklist and so we simply refuse to accept emails from them.
Our servers actually tell the sending server there's "No such user here" which is the best strategy to stop the server trying to resend the spam.

The organisations that run these mail-server blacklisting services are very good at it: a new rogue server can be listed within an hour, and a genuine server that has been compromised but has now recovered can also be de-listed within an hour.
Mail-servers aren't blacklisted by the country they're in, because they have a dynamic IP address or an incorrect, or missing, Reverse DNS record, but simply by being identified as having sent out spam and so this doesn't lead to genuine emails being falsely identified as spam.

If your company is drowning in spam, or you current anti-spam measures aren't working then give our system a try

These are the advantages:-

1 -

A dramatic reduction in the amount of spam arriving in users' Inboxes - but not quite a total elimination yet.

2 -

A system where you can easily identify and recover false positives.

3 -

There's no need to subject new senders to an authentication process before their email will be delivered.

4 -

The hordes of spammers will no longer be banging on your door, wasting your firewall and server resources plus chewing up your Internet bandwidth.
The changed MX records will have sent them all away to our servers to be dealt with.

5 -

Because of the way our anti-spam system works, you automatically get
Lost Email Protection included, detailed elsewhere on this page.

Our spam filter is very fast so the delay in routing emails via our servers and then onto yours, instead of your server accepting emails directly is usually no more than 1 minute.


We offer Anti-Spam filtering as part of our Ring Fence service.
Email, call 0800 634 9870 or fill out this webform for a free 1 month trial.

^ Top of Page ^

Paraphrased quote from Sir William Blackstone


Every email that passes in and out of our mail-servers is virus-scanned.


Anti-Virus service:

(More details...)

When an infected email is found it's simply deleted.
No email with a virus attached will have any legitimate content.
We don't send an NDR (Non-Delivery Report) or other notification to the sender or recipient.
The sender's address will have been forged, you don't need to know about yet another attempt to send you a virus email and so we don't want to waste any more Internet bandwidth for the sake of a virus.

As a second line of defence, we also perform "Pre-emptive Virus Protection".
This means deleting emails with file attachments of the types used, almost exclusively, for transmitting viruses.
In this way we provide protection against new viruses which our virus scanner doesn't yet know about.

These are the attachments types that we currently block:-

ade adp bas bat chm cmd com cpl crt exe hlp hta  
inf ins isp js jse lnk mbd mde msc msi msp mst  
pcd pif reg scr sct shs shb vb vbs vbe wsf wsh wsc

The file-types filtered out by our email servers could, if double-clicked on, cause Windows to open the file in a program that will then automatically execute code to install a virus or perform some other undesirable action.

All other file types, including DOC, DOCX, XLS, XLSX and PDF files, are only deleted if they are determined to be carrying a virus.

Microsoft Office files are not so safe, and they have been known to carry macros that act like viruses. However, if they get the all-clear from our virus scanner, we let them pass as it wouldn't be practical to block such popular files on the basis that they may contain an, as yet unknown, macro virus.

It is highly unlikely that you would ever want to send or receive files of the types blocked by our mail-servers.
EXE and MSI files may be used legitimately to send software installation programs but it is too risky to allow them to pass.
If you do want to send someone an EXE file we advise that you put the EXE file inside a ZIP file and attach the ZIP file or you could change the file extension name to TXT before you attach it and let the recipient know to rename it back to EXE after they've received it.

Although there are many examples of ZIP file email attachments containing viruses, we do allow them to pass if a scan of the ZIP file's contents doesn't show any viruses

Remember that all commonly used file extensions are allowed to pass via our mail-servers after virus scanning. This includes DOC, DOCX, XLS, XLSX, PPT, PPTX and PDF.

We include virus-scanning as a free extra to all the services that involve your emails passing in and out of our servers.

Finding viruses in emails is relatively easy and reliable compared to determining which emails are spam.
There are, however, many emails around that do not contain viruses and are written in simple, plain non-spammy language which, however, contain a link to a webpage which will try and trick you into downloading a virus, spyware program or revealing personal information.
Some of these email will be caught by our spam filter but others will get past our filters and so you still need to employ the following protective measures on your PC to be completely safe:-

1 -

Real-time Antivirus Protection

2 -

Anti-Spyware protection

3 -

Common sense

And, by the way, we will never send you emails saying that unless you click on a link and update your details we will suspend your account.
In fact you should treat any email, claiming to be from us, that you weren't expecting, as suspicious.


Anti-virus scanning comes free as part of our Ring Fence service.

^ Top of Page ^


Scanning for viruses off-site means infected emails never get to your network

How Does the 1 Month Free Trial Period Work?

Just like you would expect it to.

You contact us, giving details of your company and let us know the service you want to try out - a simple email will do, or you can use the web-form below.
Otherwise you can phone us and we'll be happy to discuss any aspect of our services or charges.
We then go ahead and set up an account for you on our servers and, if necessary, assist you in changing your MX records and making configuration changes to your mail-server, email clients and maybe your firewall.
We aim to have your trial account setup and working within 2 hours of you contacting us, during normal business hours.
All this without you making any form of payment or commitment to us.

Towards the end of the trial period we'll email you to ask if you want to continue using our services, and give you payment details.
If you do want to continue, make a payment to us and we'll leave things as they are.
If you don't, we'll co-operate in setting your email system back to how it was before the trial began without causing any disruption to your email service.
Email, call 0800 634 9870 or use the web-form below to request a free trial of the services detailed on this page.



Company or  

Phone Number:

Email Address:



^ Top of Page ^


© 2021 Arrowmail Ltd, a UK-registered company, number 4079706, registered VAT Number GB 895 0987 60
We welcome any comments about this website, good or bad. Send them to