This is curious and I have not seen this before. Version 4.5 was built with VS 2012 / .NET 4.5.
So there should be no reason for incompatibility or a migration to start.
Could it be that you are trying to open the older Patterns in Action 4.0 version rather than 4.5?
Is there anything else you have installed, perhaps another MVC version or the VS 2013 preview?
Jack Poorte, Aug 24, 2013