title: Visual Studio crashing when trying to diff or compare files
body: <p>I'm using TFS for source control and the other day I undocked my laptop while running VS. I couldn't connect to the internet and then unfortunately there was an unexpected shutdown. Since then I have not been able to go into pending changes and compare the file to it's previous version. When I do, it crashes Visual Studio.</p>
  
  <p>I can change the user tool in Options > Source Control > Visual Studio Team Foundation Server to use a third party diff checker and it works no problem. However, I've gotten used to Visual Studio's diff checker and would like to continue using it, if only because it doesn't open a separate window to diff in.</p>
  
  <p>Since I'm not sure as to the source of the problem, my question is two-fold:</p>
  
  <p>First, how do I fix Visual Studio's diff checker and stop it from crashing every time I try to compare with previous version.</p>
  
  <p>Or, if the issue lies with TFS, why is it crashing and how do I fix it?</p>