What is the version of SEPM are you using as older version of SEPM used to show 64 bit Clients in Tamper Protection off ( Tamper Protection is not installed on 64 bit clients -Not compatible)
So if you upgrade to MR4MP2 or MR5 this should be resolved.
The notification you are getting would be only reporting 64 bit clients
64-bit clients are sending Tamper Protection status to Symantec Endpoint Protection Manager as "Off" rather than as "Not Installed."
Fix ID: 1412863, 1098328
Symptom: Symantec Endpoint Protection Manager shows Tamper Protection as Off rather than as Not Installed.
Solution: Added new interface registration information to the installer.
This was fixed in MR4 = 11.0.4000.xxxx
Are u running MU5 and still getting the above message?
If you want to analyze these logs manually, you can go to Monitors->Logs->Computer Statuts Logs-> Compliance Options
Check the box for tamper protection is off and view logs. You can see the computers that are being shown in the report.
Currently there is no option to clear Tamper protection off status notification in the home page. You can add it as an idea in the idea section.
Please don't forget to mark your thread solved with whatever answer helped you : ) Thanks & Regards Aravind