Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.
This is a classic unhelpful error and nightmare. Anyway, when publishing a mvc 3 application you do not have all the requored mvc3 files on the server that is hosting your site.
The best advice I got and what actually solved the problem can be found here.
Hope it helps!
Ok, so none of the “copy local” worked for me. What did was using the deployment package that is build through my Visual Studio Solution and deploying to IIS. finally worked.