title: Why is VisualStudio looking for this lib file? LNK1104 error
body: <p>We have a large project using VS2008 and boost 1_42.  I'm trying to upgrade to VS2010 and boost 1_44.  I installed VS2010 and boost 1_44 and converted the project.  Now I am trying to build, and everything compiles, but fails when linking:</p>
  
  <p><code>LINK : fatal error LNK1104: cannot open file 'libboost_thread-vc90-mt-1_42.lib'</code></p>
  
  <p>I have changed the include and lib directories to point to the new boost 1_44 files and I have renamed the old boost 1_42 directory.</p>
  
  <p>Why is the linker still looking for a vc90-1_42 file, when it is only using 1_44 headers?  Is there a way that I can determine WHY the linker wants this file?  The linker obviously thinks it needs the file, but why?</p>
  
  <p>I have cleaned the project and I am re-building to ensure any old build files are erased.</p>