You can create 2 different reports in Symantec Messaging Gateway 10.6.x:
Above reports contain following statistics, which contains total number of messages processed by SMG:
From time to time, former one becomes greater than later.
This phenomenon occurs in case that following scenario:
In the above mentioned scenario, re-scan of the other scanner is counted and reflected in [Messages Processed] value in Email Messages Summary report.
On the other hand, re-scan is not counted in [Processed] column in Email Messages Summary report.
Control Center monitors multiple scanners
As seen, [Processed] counts one message as one and [Messages Processed] counts every scanning in the whole scanner group, which results in different number in the same deployment.