title: Msbuild fails to compile a Silverlight solution/project
body: <p>I can't seem to compile the silverlight 3 project from the command line. It comes back with </p>
  
  <blockquote>
    <p>MSBUILD : error : Test page creation failed. Unknown error "-1".
    c:\WINDOWS\Microsoft.NET\Framework\v3.5\Microsoft.Common.targets(3329,9): error
     MSB3491: Could not write lines to file "obj\Debug\HeadsetClient.csproj.FileLis
    tAbsolute.txt". Unknown error "-1".</p>
  </blockquote>
  
  <p>Everything else works great on the machine - VS2008 is able to compile everything fine.</p>