I think its your registry.
Start the computer by using the Windows CD-ROM or the Startup disk.
When you see the "Welcome to Setup" message, press R for "repair."
Press C to run the Recovery Console tool.
Select the installation that you want to repair.
Type the administrator password. If this is a domain controller, you need to supply the password for Directory Services Restore Mode.
Log on to the Recovery Console tool and type the following commands:
ren system system.old
ren system.alt systemalt.old
Copy the backup of the System hive from either the %SystemRoot%\Repair folder or the %SystemRoot%\Repair\Regback folder if you run the Emergency Repair Disk Wizard from Windows Backup and Recovery tools.
You will need to restore the most recent copy of the System hive. Any programs that run as a service or hardware device drivers that you installed since you last ran the Emergency Repair Disk need to be re-installed.
To copy the default System hive, type the following command:
copy c:\winnt\repair\system to copy the default system hive
To copy the System hive that was backed up the last time that you ran the Emergency Repair Disk Wizard, type the following command:
After you run these commands, type exit at the command prompt to restart your computer.