title: Visual studio doesn't recognize namespace inside same project
body: <p>The problem that i have is that when i open the solution that i am working on, in some files it will not recognize a namespace even thought that namespace is part of the same project and the solution builds fine. I could get rid of this problem by deleting my .suo file in the solution root folder but it is getting annoying to delete the .suo file every time i load the solution, plus i like the options that visual studio remembers the documents that i had opened when i closed the solution. I have heard that this may be caused by an extension but i disabled all the extensions and it still happens.</p>
  
  <p>I am using visual studio ultimate 2013. I am working on a big solution that is connected with tfs and many peoples are working on it.</p>
  
  <p>Does anybody have any idea why this is happening?</p>