Activating a special log file for advanced error searches (XP & Vista)

To be able to get a better idea of the cause of an error, e.g. in case of a crash, you need information about all actions related to user profi les and system guidelines. Under Windows NT 4, you could exchange the ‘userenv.dll’ file for a special Debug version and create a log file with that for finding the error.
The operating system logs the paths of the instructions and settings in the user profiles and system guidelines. Since Windows 2000, this function is provided by default and can be easily activated in the Registry.
Access the registry editor by going to ‘Start | Run...’ and typing ‘regedit’ followed by ‘OK’. In Vista, you can directly enter the command in the search line of the start menu and press the [Enter] key. Navigate to the key ‘HKEY_LOCAL_MACHINE\ Software\Microsoft\WindowsNT\ CurrentVersion\Winlogon’. Then create the ‘UserEventDebugLevel’ entry with ‘Edit | New | DWORD Value’, open it by double-clicking, and fi ll its ‘Value’ with one of the following parameters:

Hex-Value                  Result
10001             Log file with default output
10002             Log file with extended output
20001             Debugging file with default output
20002             Debugging file with extended output

After restarting the machine, you will fi nd the desired information saved in a log fi le named ‘userenv.log’ in the ‘Debug\User Mode’ directory under your Windows folder. You can delete the entries or change the ‘Value’ to ‘0’ in ‘UserEventDebugLevel’ to stop Windows from creating any further logs.