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

Similar to Benoit's answer but doesn't require any tool installation, you can use tasklist (task manager) command at the command line with the '/m' switch to get a list of processes using the dll:

tasklist /m mylocked.dll

I saw some posts indicating you have to do it from the directory of the offending dll, but I haven't found that to be the case.