Hello,
Did you check the above provided links?
I would suggest you to work on both these Articles:
Symantec Endpoint Protection Manager 12.1 console home page showing Security Status - Attention needed
http://www.symantec.com/business/support/index?page=content&id=TECH164272
SONAR Definitions are not updated on SEP 12.1 Clients.
http://www.symantec.com/docs/TECH178125
and then Configure SEPM to remove clients which have not connected within a specific number of days.
- Open SEPM and select the Admin panel.
- Click on Servers
- Right click on the Site where your management servers are located and choose Edit Properties
- Check "Delete Clients that have not connected for __ Days"
- Enter a value for Days.
- Click OK.
Hope that helps!!