Been running into this problem lately... When debugging an app in VS.Net 2005, breakpoints are not connected. Error indicates that the compiled code is not the same as the
I've had a similar problem in the past.
It was solved by closing Visual Studio and deleting the temporary ASP.NET generated assembly files for the project under "C:\WINDOWS\Microsoft.NET\Framework{framework version}\Temporary ASP.NET Files", re-opening the project.
Read the post here and the comments to resolve it.