Could not logged in my domain control

[theone]

hi,
i m facing some prob in my domain control its restarting time to time and afer some time we lost r active directory and when i restored it from my backup than it show me another message " LSASS.EXE - SYSTEM ERROR
Secuirty accounts manager initialization failed because of the following error:
The security ID structure is ivalid. Error Status: 0xc0000078. Please Click OK to shutdown this system and reboot into SafeMode
Check the event log for more detailwd information. "

Any kind of advice would be accepted.

Thanx