is there a log that registers when someone modifies bad and good senders list?
Check this thread may help you.
Thanks In Advance
Message Audit logging is to see what actions the SMG took on a message or connection attempt, not track changes made to the SMG.
Unfortuantly the SMG does not have a log for settings changes made by admins. So it would not be possible to determine who added an item to the good/bad senders lists ot other changes.
There is an Control Center Admin Event log available that logs some changes, but allowed/blocked lists changes is not part of it. It was initially intended to more fully audit admin events, but higher priority changes have pushed it in the background.
The log can be found via:
Status > Logs > Component: Control Center
You may need to change the time range, but the logs will appear as Brightmail_Admin_Events.[date].log. If additions to what is audited is wanted, it may be worth it to create or add to an Enhancement Request. To view current enhancements, use the following URL and select Messaging Gateway as the product:
To enter a new enhancement, log in to Symantec Connect and click Create Content > Ideas.