Tuesday, February 12, 2013

VS2012 Reference Has Yellow Triangle

This seems to be a common problem where a reference to another project has a yellow triangle on it.  Like this:

Check your warnings:

In my case the project targeted had a .NET library set to 4.5 and my main project had a .NET of 3.5.  The warning, however, gives all the details needed:


For me, the project in question was created with .NET 4.5 automatically, so I had no idea what was going on when I ran into this original problem.  To fix it, right click on the project and select properties:

Then change the ".NET Framework" dropdown to the same version as all other projects.  You'll be presented with a warning that the current project should be closed and re-opened after changing.  Click the "Yes" and continue.  Then close and re-open your solution.