Question : LSASS.exe cpu usage

TaskManager shows LSASS.exe cpu usage around 50% on our servers.  Anyone know what this is and how to eliminate the cpu usage?

Answer : LSASS.exe cpu usage

The LSASS, Local Security Authentication server process, is an NT service that handles requests from WINLOGON and calls the appropriate authentication package. It verifies passwords stored in the SAM. Upon succsesful authentication, LSASS generates an access token object that contains the user's security profile.

Try reinstalling service pack 4 and see if that fixes your problem.