I have a .NET 4.0 dll project that is being called by a .NET 2.0 project. Is there a way to reconcile the difference in framework?
Not that way round, no. The .NET 4 CLR can load .NET 2 assemblies (usually - there are a few exceptions for mixed-mode assemblies, IIRC), but not vice versa.
You'll either have to upgrade the .NET 2 project to .NET 4, or downgrade the .NET 4 project to .NET 3.5 (or earlier).
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