title: VS2010 not opening files when opening a solution
body: <p>When I open my project in VS2010 it doesn't re-open the files that I had open last time I closed the solution (and I would like it to).</p>
  
  <p>The worked until last week, now it doesn't work for any of my solutions.</p>
  
  <p>I've read elsewhere that this information is kept in the SUO file.  I've checked, and the SUO file is there.  If I delete the SUO file it is re-created, but that doesn't fix the problem.  The selected startup project is also kept in the SUO file, and that is being remembered correctly when the solution is re-opened.</p>
  
  <p>I can't find an option that controls this behavior.</p>
  
  <p>Any ideas for what to check?</p>