"The breakpoint will not currently be hit" "The source code is different then the original version"

Today, I was debugging an ASP.NET website. I was at a breakpoint when a co-worker called me over to their desk to help with a defect they were trying to reproduce.

I needed to use remote desktop to look at something on my own machine, so I did so. While I was accessing it via remote desktop, my Visual Studio decided to crash.

Aftwerward I started seeing the following on breakpoints I was trying to hit:
"The breakpoint will not currently be hit. The source code is different then the original version"

I thought that a reboot would help, but to no avail.

After talking to another co-worker that had seen it in the past, he informed me that he fixed it by deleting all of the Temporary ASP.NET Files.

Sure enough, it worked like a champ. However, I had to shut down anything that had handles on those files (like the ASP.NET development server, Visual Studio, etc.) before I could complete the delete.

So to fix the problem:

1. Close out Visual Studio and make sure any instances of ASP.NET development server are closed as well.
2. Delete everything from "C:\Windows\Microsoft.NET\Framework\v.2.0.50727\Temporary ASP.NET Files" (where v.2.0.50727 is the version of the .NET Framework your site is running on.)

Hope this helps someone else... it sure helped me.