Windows Vista Error : Failure – Security Options

After updating windows vista become damn slow. When press ctrl+alt+del it gives error message : “Logon Process has failed to create the security options dialog” Failure – Security Option.
 
To resolve this problem , reboot in safe mode —
 
Go to Start — Run – Msconfig — Services — Disable the service named  SUPERFETCH.  Now restart the computer.
 

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