.NET code download has very good code for writing errors to a file, and it's explained in the .doc file that comes with the code. It only took a short time to modify that code for C#.
Be advised you have other areas to work on to make it "friendly" to hosting company sites:
1) It'll run from the root web dir, not a virt dir named ThePhile. These changes must be done in many code files, and in the DB. The most elegant solution is to store the path in one place (a .config file, or hard-coded in a class file). The DB should NEVER hold absolute dirnames in records.
2) You MUST add forms-based authentication to File Manager, and fix all "sensitive" forms (admin forms) to validate security. You'd be surprised how many of them do not! The advertisement admin page lets EVERYONE in. User admin is generally safe through the front door, but anyone can hit this page:
3) Some areas for possible speedup: use Server.Transfer instead of Response.Redirect for all transfers to local pages ending in .aspx - this avoids a server roundtrip. Consider not using "SRC=" to register user controls. We should be able to use a classname instead (we can deploy compiled controls)
4) Put a limit on password retries, add password expiration, add a "must change" flag. IMPORTANT! Log all password failures (ideally include the user's IP)
5) The rest of my ideas are more trivial. Like having different categories of ads, and letting users select which Forums they want to participate in. Once they pick a forum, you know what kind of ads to target at that user. A DVD-only user doesn't want to see ads for books. Don't ask users for email addresses for use in forums, and remove the icon for email addresses.
6) The dumb little navigation menu on the right has always bugged me! Consider using this freeware menu:
Ideally we could dynamically create this menu. Some users might have some priviledged function that we could add to their menu after they log in.