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Preventing Spam

Spam is an ever-increasing issue and we take a number of measures to reduce spam. While it is impossible to have 100% Spam Free email below are just some of the measures we take.

Anti-Spam Measure

What it does

HALO Check

Any mail server trying to connect to our server must pass a HALO identity check. If the server fails this check then it is prevented from sending any email to our server.

RBL Check

The IP address of the sending mail server is checked against a Realtime Blacklist of known addresses sending spam. If the server fails this check then it is prevented from sending any email to our server.

SPF & DKIM Check

The domain name that the email is from is checked for an SPF of DKIM settings. If the sending mail server does not match these settings the email is rejected.

Spam Assassin

Every email is checked by the spam filter on our server and scored for possible spam. If the score is above a specific number the subject is marked as ***SPAM***. If you access your mailbox via IMAP we can turn on a filter to move these emails into the Spam folder.

Content Filter

We have a number of filters checking all mail. If the email matches that filter it is rejected.

Filter Rules

In the webmail for each mailbox the user can setup filter rules. If you get repeat spam from the same source or with the same subject you can setup a filter rule to move the email into the spam folder automatically.

 

Setting your Spam Assassin Level

One of the account-level Spam detection systems we use is Spam Assassin. This scores your emails and if an email is above a certain score it is tagged as Spam. You can then set the server to move these spam messages into a junk folder.

To set this go to the webmail, at https://mx1.3legs.com/webmail, and log in with your username and password. Now go to the settings, choose accounts and then Spam Protection.

Here you will see a drop-down menu to choose the Spam Protection level you want and a toggle switch to enable having these emails moved to the Junk folder.

Spam Levels

By default, we will see email accounts to Normal. The table below shows you the different Spam Levels you can choose. Just remember the more aggressive the spam level the higher the risk of legitimate emails being marked as spam.

Spam Level Tag Level Tag2 Level Kill Level
Normal 1 5 50
Plus 1 4 30
Enhanced 0.5 3 30
Extreme 0.5 2.5 30

 

Tag Level is simply a level where the email could be spam. These are not flagged as spam or moved.
Tag2 Level marks the subject line with ***SPAM*** and if the "Move spam emails to junk folder" is enabled the emails are moved.
Kill level is the points score the email needs to reach before it is simply deleted.

 

Remember the more aggressive the spam policy the more likely there is a false positive. Always check the Junk folder, this may be different to the Junk/Spam folder that your email application may create.

Greylisting

An additional measure we can enable is Greylisting, here the connecting mail server is checked against an internal database of recognised mail servers. If the sending server is not found the email is temporarily rejected. Most legitimate mail servers will try to send the email again at which point our server will accept the email. Mass mailing spam servers will often not bother retrying so this is an effective tool to reduce spam. The downside with enabling this is that it can take a few minutes longer to receive legitimate emails. Contact us if you wish to have this enabled for your mailbox.

Pre-Server Filter

These are all the on-server Anti-Spam options if you wish to add further anti-spam measures then we can provide a pre-server filter solution. With such a solution all email to your domain name is sent to this service it will then perform anti-spam filter checks and deliver clean email to your mailbox on our server.

All email for your domain name needs to go via this service and it is charged per email address. Any email sent to an email address not paid for is discarded.

If you are interested in this service then please contact us.