Information
Spam Confidence Level (SCL) is a rating assigned to incoming email messages by the Content Filter agent in Exchange Server. It is a measure of the likelihood that an email is spam based on various content analysis techniques and spam detection algorithms. The SCL value ranges from 0 to 9, with 9 being the highest level of confidence that the email is spam.
Ensure SCLQuarantineEnabled is set to True
Rationale:
E-mails with a high Spam Confidence Level (SCL) will be quarantined. This involves moving it to a designated quarantine e-mail address, separating it from the regular inbox of the recipient in order to prevent users interacting with malicious e-mails.
Impact:
False positives may occur when setting SCLQuarantineThreshold to lower values.
Solution
To implement the recommended state, execute the following PowerShell cmdlet:
Set-ContentFilterConfig -SCLQuarantineEnabled $true -SCLRejectThreshold 8 -SCLQuarantineThreshold 6
NOTE: The SCLRejectThreshold must be greater than the SCLQuarantineThreshold when enabling the Quarantine and is why it is changed in this instance.
Default Value:
SCLQuarantineEnabled: False
SCLQuarantineThreshold: 9
SCLRejectThreshold: 7