How to debug a vb dll for asp

1. in iis, create an independent application pool for the web site.
2. enable asp server-side and client-side script debugging (properties - home directory - configuration - debugging).
3. unenable anonymous access (properties - directory security - authentication and access control).
4. set breakpoint in the code of the dll module and run it in visual basic ide.
5. run asp code (web site).

do not compile the code and register the dll before debugging. or restart iis and delete the dll file.