title: VS2010 pdb lock error when modifying a css file
body: <p>In one of my VS projects I get this error when I modify a css file in a App_Themes catalog in runtime.</p>
  
  <blockquote>
    <p>CS0042: Unexpected error creating debug information file '[..]\Temporary ASP.NET Files[..]\App_Theme_MySite.pdb: The process cannot access the file because it is being used by another process.  </p>
  </blockquote>
  
  <p>I've used the Process Explorer and concluded that the file is being locked by the devenv.exe file.</p>
  
  <p>In order to proceed I have to restart the entire project. 
  It only happens in this one project and I have been unable to find what differs from other projects where I don't have this problem.</p>
  
  <p>Solution running, css modification, solution crashes.</p>
  
  <p>Any ideas?</p>