title: Error Upgrading To .NET 4.5
body: <p>I'm trying to upgrade from VS2010 .NET 4 to VS2012 .NET 4.5 and I'm getting the following error in each Project that I've set to .NET 4.5 when they try to build.</p>
  
  <p>The expression "[Microsoft.Build.Utilities.ToolLocationHelper]::GetPathToStandardLibraries(.NETFramework, ?, '', '')" cannot be evaluated. Version string portion was too short or too long.</p>
  
  <p>I can't find any references to this in my code and the msdn reference for the function doesn't provide any hints (<a href="http://msdn.microsoft.com/en-us/library/hh135279.aspx" rel="noreferrer">http://msdn.microsoft.com/en-us/library/hh135279.aspx</a>).</p>
  
  <p>Anyone seen this before or know the solution?</p>
  
  <p><strong>Edit</strong></p>
  
  <p>The solution listed here doesn't seem to work. <a href="http://social.msdn.microsoft.com/Forums/da-DK/vseditor/thread/8ca4a9b0-742d-487d-ab8c-6c3a80cffd40" rel="noreferrer">http://social.msdn.microsoft.com/Forums/da-DK/vseditor/thread/8ca4a9b0-742d-487d-ab8c-6c3a80cffd40</a></p>