I\'ve managed to get myself in a state where I\'ve no instances of devenv running, but still a MyApp.vshost.exe in the background (no visible windows or consoles).
I had the same problem while working on a project with .NET 2.0 as target framework.
Temporary changing the target framework to .NET 4.0 client did the job for me.
However, Iam unsure how this is (is it?) related to the file lock issue.