title: ResolveComReference Invalid argument. Parameter "ItemSpec" cannot be null
body: <p>I am in the process of upgrading a project to .NET 4.0 and I get this error when I try and build the solution: Invalid argument. Parameter "ItemSpec" cannot be null.   c:\Windows\Microsoft.NET\Framework\v4.0.30319\Microsoft.Common.targets  1558    9</p>
  
  <p>Is there a way to find out what is being passed as null to the ResolveComReference task?</p>