Visual Studio 2010 not recognizing .NET framework 4.0.3

Question

When I try to open a solution I'm getting this message

The C# project "X" is targeting ".NETFramework, Version=v4.03", which is not installed on this machine

I installed the upgrade from here but that didn't fix the problem. I restarted the machine just in case but no luck

Does anyone know what's missed?

Answer 1

This is resolved, I needed to install Multi-Targeting Pack for Microsoft .NET Framework 4.0.3 (KB2600213))