Changing the config file won't give it permission to do something that it's not allowed to do.
I think this is the common error relating to creation of an event source, but this might be a little different.
In any event, the account used to run your application (ASPNET on Win2k and XP) does not have permission to do the registry access needed by a certain operation (most likely creating an event source or something similar).
This is discussed in the README.HTM file in the code download. They explain how to run the application under the SYSTEM account instead of ASPNET.
I prefer to use a different solution than the one given there, because this is entirely unacceptable for production deployment. I prefer to create the event source in a console mode program (because your user account likely has permission to do this), and then run the application under a lower priviledge account (like ASPNET). This makes for a much safer system in case a hacker might gain access to your system.
I posted another message here with code to do this - look around and you'll find it.
The best solution in my opinion is to remove all use of event sources, and log to a file instead. This was done in the
VB.NET code download. This is the only suitable option if you want to use a low cost hosting company, because they won't give you registry access.
Eric