All incoming emails first pass through our spam filters before being delivered to your mailbox.
These settings are combination of our settings and yours. |
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Step 1: Our rules
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| We check that the email is composed correctly (a common fault for some spammer) and that the sender is a real email server. Usually spammers don’t use a real mail server system which sends and receives mail – they only need to send. We then check the sender, any email addresses and URL’s within the email against various databases of known spammer’s and website’s that use spamming. These would include the popular faked ebay admin pages, fake bank logins, commercial viagra sites etc etc. The databases are updated very regularly. We also have our own database and share this with many ISP’s worldwide. We check the content and composition of the email. The system looks for common words and word strings as well as common attachment sizes, quantity of text, common themes, number of images, number of non-dictionary words (it has almost every language in it’s dictionary too).It does not simply look for words like “viagra” as people sometimes use these in normal emails and spammer’s very rarely use the word like this. Again, a complex database of algorithms and word patterns are maintained by us, and various ISP’s which use the same software as us worldwide. The system is clever enough to spot a spam email and automatically profile the email and add it to the database. Our spam system is looking for emails pretending to be something they are not – these are more often than not spam… There are several other tests, over 1000 in total performed on each and every email. Including SPF – Sender Permitted From. SPF basically is a field added to a domains DNS data that tells the internet it’s email system IP addresses and urls. For example, only mail.macace.net at 212.87.65.109 is permitted to send mail ending in @macace.net. |
Step 2: Your Settings
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| As well as controlling what happens to a message after it has been scored for “spaminess” (HOLD, REJECT or VANISH) you can control spam by the Friends system – a whitelist and a blacklist for emails. Whitelists, or “Friends” bypass the spam tests and always get their emails through. By default, anyone you send a message to will be added to your “Friends” list (you can turn this off though). Blacklists are automatically rejected – unless you have a specific use for this we don’t recommend using this for spam. You can also set the system to challenge people not on your Friends list. It sends them an email to reply to before allowing the original message too. In theory only real people with reply, not spamming systems. |
Step 3: Friends
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| Automatically stores email from unknown senders in your ‘pending’ folder awaiting a reply to a confirmation message. This helps check they are a real person and not just a spam program. |
Step 4: Spam Filtering
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| Automatically stores email that is suspected to be spam in your ‘held’ folder for 2 weeks. You can go to your ‘held’ folder to release messages wrongly identified as spam. |
Step 5: SPF filtering
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| This blocks most spam by rejecting emails where the sending machine is not the mail server for the domain used in the from address. |
Step 6: Friends
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| Messages from people on your friends list are identified and passed directly to inbox skipping the remaining spam filtering steps. |
Step 7: SPF (Sender Permitted From)
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| Determines whether the connecting machine is allowed to send email for the domain in the ‘from’ address. If the domain has not yet set up SPF records a best guess is made to see if the machine is reasonable – generally this will permit the email unless the sending server does not respond correctly or the domain IP address is different to email we’ve received recently. |
Step 8: Accept Rules
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| The allow exception rules are then processed, these are used to bypass normal spam and friends filtering. Users should be careful setting up such exceptions. A exception might allow anything with my secret password in the subject, or from my boss email address. |
Step 9: Filters
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| Next the users filtering and exceptions rules are processed to check for special rules like, move incoming mail to particular folders. |
Step 10: Spam Rules
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| Next the step is the “adaptive spam detection system”. This is used to determine the spam score of the email. The users spam rules are then be applied to determine if the email is to be marked as spam, placed in the held folder, bounced back to sender or deleted. |
Step 11: Friends
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| The friends challenge response system is then applied. This will place messages which match the friends setting, in the pending folder while a request for confirmation is sent back to the sender. Friends confirmations can be used for all unknown senders, just for suspicious looking emails or no-one. Recommended setting: is require confirmation for any email with spam rating of 1 or more. Responses to confirmation requests are handled in step 3 and will release messages from the pending folder into the inbox. |
