Visual Studio 2012 professional ihangs trying to load symbol

i am working on asp.net mvc5 web application inside visual studio. now VS was a bit slow , so i run the following commands:-

devenv /resetuserdata

now the Visual studio will hangs for a while trying to load the following dll :-

Image may be NSFW.
Clik here to view.

after that it will show "this item does not support previewing" and VS will hangs ..

can anyone advice on this please? although the dll file it is trying to load already exists ...