I get this error in Visual Studio 2008 when developing an ASP.NET web application project.
Unable to load the 'Path-to-DotNetNuke \ bin \ file.dll' help library: the process cannot access the file because it is being used by another process.
This is a DotNetNuke project with several modules. IIS downloads all assemblies from the / bin folder in the root of the application.
Projects in the solution are located in the corresponding folders / DesktopModules / ProjectName and compiled into the bin folder within the project.
The error occurs after compiling the solution and copying all the project dlls to / bin using the script. Visual Studio does not allow me to recompile, but if I restart it, everything will work fine. This is very annoying when recompiling and testing the whole solution. You must restart Visual Studio between each recompilation.
I could not find any file locks in Process Explorer when Visual Studio shows this error.
[UPDATE] There is an old MSDN document stating that you should not create all DLLs in the same folder if you link to more than 64 KB of DLLs. Partially, the document says:
This causes the build process to fail with file locking errors when the referenced build exceeds 64 KB in size.
64 DLL /bin DLL, , , , VB IDE.