If you have XP Pro, click here
For XP Home, you will have to edit the Registry - be careful if you are not familiar with the registry editor. click here
If you don't want to use this method, a semi-automated process that does the same thing is at click here - right-hand column opposite Tip #14
I would also recommend checking that you have the latest version of Nero.
Has this fault always appeared, just recently, or is it an intermittent error?