Swap the MEF loader from a general folder scan to inspecting each DLL and loading with a safe loader as per this
post on stackoverflow
Chance could also be be taken to add the option of name based filtering.
This was first seen as an issue with the move to VS/TFS 2015. The unit tests failed due to MEF failing to just load the DSL assemblies when creating the catalogued from the bin folder. The immediate fix was to use the feature to load the test DSL from a different