Messages that are rejected are ones we know are spam - these fall into three main categories:

• Emails which are malformed or are sent in a way which is non-standards compliant, these are either spam is emails being sent via a broken mail server.
• Mail from computers known to be used by spammers - we use DNSBL’s to find out if the computer sending email through our servers is a known spammer or not.
• Messages which our spam filtering software is very confident are spam, such as those which match a Distributed Checksum Clearinghouse, or have a very high combined score from all the tests we carry out.

Further to this, our software identified 6,611 emails which were likely to be spam but weren’t confident enough about to reject - these are the ones which are arrive with “***SPAM***” in the subject line.

We also identified 302 viruses in emails*; this may seem low - but this is because the majority of viruses were rejected before they got as far as the virus scanner.

Spam and virus filtering statistics for the past week (click to enlarge).

* Please note, although we do check incoming emails for viruses, we strongly advise our customers to run anti-virus on their machines, especially if they run Windows.

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Spam filtering statistics

We’ve also made further improvements to our spam filtering system over the last few days. Initial indications are that the new filtering we have put in place has made a significant improvement to our “hit rate” so we are now rejecting (rather than tagging - emails that arrive with *** SPAM *** prepended to the subject line) more spam than ever.

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Updated webmail and spam filtering upgrades

You can read more about DomainKeys at Wikipedia, or in the RFC.

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Domain Keys Identified Mail

The easiest way to avoid these scams is to check very carefully that any domain renewal notices come from us. If you are unsure, please contact us via the contact details on our website and check. The other people who may legitimately try and contact you about your domain will be Nominet, the UK domain name registry.

How to avoid these scams:

1. Ask us to enable our free WHOIS Privacy service for your domain. This hides your name, address, email address and telephone number from would be scammers and spammers. Legitimate contact can still be made via the WHOIS Privacy system.

2. Ask us to enable Domain Locking - this will prevent your domain being transferred until it is disabled again. You will always have the ability to remove the domain lock yourself from our control panel.

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Domain name renewal scams

Greylisting works by temporarily rejecting email from people who have never emailed you before. Any legitimate, standards compliant, mail server will retry delivery of the email after a short period. Many spammers use non-standard mail servers which are simply designed to “fire and forget” in order to send the most spam in the shortest period of time - they rely on volume.

This also has the advantage that it increases the likelihood that the realtime blacklist (RBL) and distributed clearing houses we use will detect any spam.

This means that the first time (and only the first time) you receive an email from somebody it may take a few extra minutes to arrive. There is, however an increase in performance on our mail servers gained by reducing the amount of spam we process. We continue to monitor the situation and will as always work to ensure we are providing the best service to our customers. Please do contact us if you think this is causing a problem for you.

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Greylisting and other anti-spam features

POP (Post Office Protocol v3 or POP3)

POP downloads email from a single folder - your Inbox. When you check your email in your mail program, it downloads the email from the server to your local computer. In most email programs, you can choose to leave the email on the server for a a number of days so you could choose to leave mail on the server for 30 days and then use our webmail to see recent email and new email when you are away from your computer. As email is moved from the hosting servers to your computers each time you check your email, it does’t use up as much of your hosting space.

POP is ideal if:

you read/reply to your email on one computer most of the time.
if you have very high volumes of email (particularly email with attachments).
you use dial up, or a pay-as-you-go internet service provider.
you only want to look new/recent email via webmail.

IMAP (Internet Message Access Protocol v4 or IMAP4)

When you access your email using IMAP, it remains stored on the server in multiple folders (including folders you can create yourself, and your sent items). This means that you can connect to the mail server from any computer and see your email in the relevant folders. Most email programs allow you to work “offline” from a local copy of your mailbox so you can still read/reply to email when you are not connected to the internet.

IMAP is ideal if:

you read/reply to your email on several computers (including via webmail).
you use a mobile email device such as a BlackBerry or our webmail service.
you don’t receive a huge volume of email, or many large attachments.
several people share a mailbox (for example a generic “sales@” email address).

As your email is stored on the server, it counts towards the space allowance on your account - if your account becomes full you will need to delete some email, download it to your computer or upgrade your account to give yourself more storage space.

Generally, we advise people to use POP unless there is an overriding need to use IMAP.

One more option… SMTP

Beyond the scope of this article, with mentioning SMTP. If your company has it’s own mail server on it’s network (such as, Microsoft Exchange), we can arrange for email for your domain(s) to be delivered and provide a backup server incase your network or server is unavailable. Please note email delivered by SMTP does not get filtered for viruses/spam on our servers - so you will need to make alternative arrangements.

Information in these guides and articles is provided free of charge and without warranty.

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POP or IMAP?

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Hosting Control Panel

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Website statistics

We’ve added some of the rules from SARE to enhance the spam scoring carried out by SpamAssassin. Along side some other small changes to the SpamAssassin configuration, we are seeing a significant improvement in the quality of the filtering. More spam is being rejected outright (rather than being simply tagged as suspicious).

We have also started using the Razor and DCC clearing houses. These work by taking checksums of certain portions of email and comparing them to recent known spam. Don’t worry, we don’t send your email or any personally identifiable information to third parties to do this - we simply send a hash or fingerprint of the information.

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Even more spam filtering updates

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Managed or self-service?