A real techie one here but useful for anyone working with vb.Net 2005 

Application: Microsoft Visual Studion .NET 2005 – Web Application

Error Message: ‘"The breakpoint will not currently be hit. The source code is different from the original version"

Symptoms:

When running in debug mode I started receiving the following message and debug points were not hit in code that I was modifying. I tried many of the suggestions on the web but eventually resorted to a methodical approach to find a solution. For some reason, changes to .aspx source files were not being compiled into the new .dll. The date and time of the .dll and debug file were updating but the changes were not being included. Debug points in non-modified code would still be hit, the output from the build didn’t list all warnings like it should/used to do.

Various things I tried but all to no avail...

A)

B)Deleting the .dll and debug files in the bin directory off the root.

C)Checking debug=true in web.config

D)Checking CopyToOutputDirectory=False on various .aspx files

Solution:

1. Right click solution in solution explorer

2. Select Clean Build from menu option

3. Check complete solution builds successfully with no error

4. Debug run the solution.

5. Simple!!

All working fine now perhaps I can get on with some real work J !!!