0
try clearing your local VS cache. find your project and delete the folder. the folder is created by VS for what reason I honestly don't understand. but I've had several occasions where clearing it and doing a re-build fixes things... hope this is all that you need as well.
here
%Temp%\VWDWebCache
and possibly here
%LocalAppData%\Microsoft\WebsiteCache
0
clean the solution file or close visual studio and restart it