Build error: “The process cannot access the file because it is being used by another process”

Question

I\'ve got a C# webforms app, that until today had been working just swimmingly.

Now today, all of a sudden, every time I try run the app, I get a file l

Answer 1

Little late to anwer, but I solve this by going to the properties of the project > tab "Debug" > uncheck "Enable the Visual Studio hosting process".