Default spam Scanning Levels

Introduction

The mail gateways are used to scan all email to uky.edu and other selected domains, and outgoing mail from some systems. Sometimes mail that is sent between systems on campus is routed through the mail gateways as well.

The mail gateways use several applications to scan incoming email and protect users from spam email and viruses. Mail entering the gateway is checked against the SpamCop Real Time Black List (www.spamcop.net) and against a local database of known spammers. The SpamCop RBL can be overridden in special circumstances.

If the sending mail host is allowed by both SpamCop and the local database then it is examined for prohibited attachments. Prohibited attachments are primarily executable files like programs and scripts, but also include other file types that can transmit viruses.

It is at this time that the spam scanning takes over. Any message containing a virus is discarded. An uninfected message is then checked and given a score that indicates how likely it is to be spam or fraudulent in some way. A score of zero indicates a low likelihood, five indicates the messages is probably spam, and higher scores indicate an increasing chance that the message is spam. If the score meets the defined threshold it is flagged by inserting "[Spam]" into the Subject header of the message. Once all checks are complete and the message is accepted it is queued for delivery and sent to the mail system responsible for the users email.

If a message is rejected an error response is generated and sent back to the originating mail system, in most cases the originating system should forward this error message to the original sender.

The mail gateways are configured with 6 spam scanning levels that users can choose to filter their email. A description of the available levels are provided below.

Table of Contents

• Accessing the mail gateway management interface.
• Opt out of spam scanning
• Tag spam - permissive, less aggressive
• Tag spam - moderate threshold
• Tag spam - moderate threshold (No Domain Restrictions)
• Tag spam - aggressive
• Reject high-scoring spam, tag other spam - very aggressive
• For More Assistance

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Management

Accessing the mail gateway management interface.

By logging into https://mg.uky.edu/ with your email userID (no AD\ or MC\ required) and password you can select one of the default spam scanning levels to check incoming email. Simply select the circle of the scanning level you prefer, and then click the Set Spam-Scanning Level button to apply the change.

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Default Levels

Opt out of spam scanning

Selecting this spam scanning level will prevent your mail from being scanned for spam email and domain mismatching and blacklisting will be ignored. With the exception of viruses and forbidden attachments, all email will pass unaltered through the mail server.

Virus scanning, and blocking of forbidden attachments will still occur.

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Tag spam - permissive, less aggressive

Selecting this spam scanning level will cause the mail gateways to flag only the highest scoring messages. Messages that are considered to be spam will be flagged as such by pre-pending "[Spam]" to the subject of the email message.
Virus scanning, and blocking of forbidden attachments will still occur.

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Tag spam - moderate threshold

This is the default scanning level.

Selecting this spam scanning level will cause the mail gateways to flag messages with a moderate score. This is most likely to catch actual spam and minimize the number of false positives.

Virus scanning, and blocking of forbidden attachments will still occur.

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Tag spam - moderate threshold (No Domain Restrictions)

This is the same scanning level as Tag Spam - moderate threshold, but with domain mismatch rules ignored. Mail from blacklisted domains is not rejected, but will likely be flagged as spam. This will result in additional spam email messages coming through the filter, but will prevent erroneous rejections for users who forward mail to their UK accounts from elsewhere.

Virus scanning, and blocking of forbidden attachments will still occur.

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Tag spam - aggressive

Selecting this spam scanning level will cause the mail gateways to flag low-scoring messages. This is likely cause messages to be falsely identified as spam.

Virus scanning, and blocking of forbidden attachments will still occur.

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Reject high-scoring spam, tag other spam - very aggressive

Caution should be taken when using this scanning level

Selecting this spam scanning level will cause the mail gateways to flag low-scoring messages and reject messages with a high score. The recipient of the email message will not be notified in the case of email rejection, but the original sender will receive a notice that their message was not delivered.

Virus scanning, and blocking of forbidden attachments will still occur.

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Notes

SPAM® is a registered trademark of Hormel Foods Corporation, which permits the term spam to be used to denote unsolicited commercial email (UCE). For more information please visit http://www.spam.com/ci/ci_in.htm

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For More Assistance

Please contact the IT Customer Service Center if you have any questions or problems while following these instructions. The IT CSC is open from 7AM to 6PM Monday through Friday. You may come directly to the CSC at 111 McVey Hall. You may also reach the CSC by phone (859.257.1300) or email (helpdesk@uky.edu).