Hello,
What version of SEP 11.x are you using??
Could you check on all group policies, Tamper protection is checked and Locked.
To check the same follow:
- Log in SEPM
- Click on Clients
- Highlight
- Click on Policies TAB on the Right hand side.
- Click on General Settings.
- Click on Tamper Protection Tab
- Make sure the Tamper protection is Checked and Locked.
- Check all the Groups and Subgroups.
When anything like this happens, you get to know on the SEPM home screen like Autoprotect -Off, Antivirus Engine off and so on..
Yes, Faster way to resolve the issue is to Uninstall them and Reinstall the same.
Check these Threads:
https://www-secure.symantec.com/connect/forums/endpoint-protection-auto-protect
https://www-secure.symantec.com/connect/forums/auto-protect-tamper-protection-intermittently-becomes-random-clients
Hope this helps!!!