C# Code Changes Not Reflected on Server in ASP.NET MVC 4

Today I ran into a problem where changes I made to my C# code were not being reflected on the live site after uploading via FTP. I checked the compiled DLL in the bin folder — the file was uploaded correctly, but the site was still behaving as though the old code was in place.

If you run into this problem, I suggest deleting the old .pdb and .dll files for your project from the server's bin folder. For example, if your project namespace is xyz, delete xyz.pdb and xyz.dll, then re-upload the new DLL from your local bin folder.

That should fix it!