Unable to copy file reference.dll to bin/reference.dll. The process cannot access the file reference.dll because it is being used by another process

Question

For one of my ASP.NET 3.5 applications, every single time I try to build the web app, it throws the following build errors in Visual Studio 2008:

Error 16

Answer 1

You could download the excellent SysInternals Handle program. This will tell you which processes have a lock on the files concerned.

If it is an external program (e.g. virus scanner/indexer) then this should help. If it just reports Visual Studio (devenv.exe) as the culprit, then it will be of less help!