Submissions for customer specific spam rules are not being accepted for all users even though the Submitter's List in the Control Center Spam - Submission Settings - Submitter's List is set to the default "Blocked" configuration with an empty block list.

This configuration should allow submissions from all email addresses but looking up the submission in Status - Submission Detail shows that the Submitter Type is "Blocked" and the Invalid Reason is "The submitter was a blocked user".

This issue is currently under investigation.

Workaround

Add an unused email address to the Spam - Submission Settings - Submitter's List - Submitter Addresses list to force SMG to synchronize the local submitter configuration with the submitter configuration stored in the Symantec operations center.