No logs on vista in program files
If you are trying to write the logs to Program Files, you should change that. Vista does not support having a user write stuff to the Program Files structure. The only way that will work is if the user turns off UAC, which isn't recommended.
The safest thing is to create a folder under the user's MyDocuments for your application, and put the logs there. (We put ours there so the user could find them and send them to us.)
You can also write to Environment.SpecialFolders.LocalApplicationData, which is under the user's profile.
RobinS.
