after removing internet security 2010 system logs off automatically

Run regedit from other machine on the same network as the problem PC.

click File > Connect to Another PC
need to be domain administrator while connecting registry of the fault pc to your pc( login as domain administrator)

Navigate to
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\

In the right pane, you should see

C:\WINDOWS\System32\wsaupdater.exe,

Change it so that it reads:

C:\WINDOWS\System32\userinit.exe