"I was experiencing the same issue on .net 2.0 website, on one page.
I fixed this by killing off the worker process (asp_wp.exe), then
deleting the website directory from the .net temp files
(C:\WINNT\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files)
and then doing an iisreset."
This worked for me as well. What is wrong do you think?