Spam Filtering

SpamAssassin spam filtering is turned on by default for all e-mail accounts. E-mail messages that score high enough to meet the SpamAssassin threshhold can be either flagged and stored in the e-mail box or automatically deleted at the server. Because of the very low level of false positives and the fact that e-mail addresses can be whitelisted, we recommend that messages that meet the SpamAssassin threshhold be automatically deleted at the server.

• Domain administrators can optionally configure spam filtering for all e-mail boxes in a domain.Note - the domain administrator can be EPCS or this function can be done by the domain owner.
• Individuals can optionally configure spam filtering for their individual e-mail box.

Spam filtering can be enabled or disabled for individual e-mail boxes. The spam threshold can be modifed for each individual e-mail box (although we recommend that the threshold be left at it's default value, 7). E-mail messages that exceed the spam threshold can be automatically deleted at the server (recommended) or flagged and placed in the e-mail box. E-mail addresses can be exempted from spam filtering by placing the address in the Whitelist for the e-mail box.

Individuals who may want to configure their own e-mail box parameters should contact their Domain Administrator. Domain Administrators who may want to configure their e-mail boxes should contact EPCS.

Not all messages score high enough to be flagged as spam, but all messages are scored by SpamAssassin. To view the score for unflagged messages

1. Open the message in Microsoft Outlook or Outlook Express
2. Click File / Properties / Details

The score is labled "score" in a header line that looks something like
X-Spam-Status: No, score=2.4 required=7.0 tests=AWL,BAYES_00,HTML_MESSAGE autolearn=ham version=3.0.5

In the above example the spam score is 2.4 and the threshold for flagging the message as spam is 7.0.

Greylisting is a no additional cost spam filtering option offered by EPCS.

Greylisting improves spam filtering considerably. When turned on for a domain, the greylisting process reduces spam uncaught by SpamAssassin at least 50%.

Greylisting can be turned on or off for all the e-mail addresses at a domain, but cannot be turned on or off for individual e-mail addresses.

When greylisting is turned on for a domain, the first e-mail sent From: an address is delayed from one minute to several hours. However, once the address is greylisted, subsequent e-mail From: the address is not delayed.

EPCS has detected no examples of false positives (rejection of messages that are not spam) when greylisting is turned on.

If a From: address has been whitelisted, the greylisting process will "pass" e-mail From: the address. Maintenance of the whitelist can be done via a web page login for the individual e-mail account.

A good explanation of how greylisting works and why it works can be found on Wikipedia.

To order greylisting for a domain, contact EPCS.