Fun error we get in aspdotnetstorefront all the time! It could happen when you recompile the website, or when you publish to a staging or live server. The easiest way to handle this is to open the task manager and kill the asp_net worker process. This is faster than an iisreset, which is the next step to take if killing the process does not remove that error.
Don't bother with what the error message says, it's just a hiccup when the app starts thinking about an exit strategy for the war in Iraq.