Can't load EntityFramework.dll 5.0.0.0 inside Visual Studio 2013 extension

Question

I'm writing a Visual Studio extension which depends on EntityFramework 5.0.0.0. I included EntityFramework in my project. When I install my extension, my extension's DLL appears in VS extensions folder, and EntityFramework.dll appears with it as well.

However, when I run my Extension in Visual Studio 2013 (update 5), it can't load EntityFramework: System.IO.FileNotFoundException: Could not load file or assembly 'EntityFramework, Version=5.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies. The system cannot find the file specified.

Looking in Process Monitor, I saw that when I run my extension, VS2013 tries to load EntityFramework from a different path, which has it in a different version - 4.2. I'd expect VS2013 to continue to search for EntityFramework, and find it in my extension's folder, like it does for other dlls included in my extension, but it doesn't.

In VS2015, VS does manage to load EntityFramework 5.0.0.0, but it does so also from yet another different path.

Why doesn't VS2013 continue to search for EntityFramework in my extension's folder?

Answer 1

You need to specify a ProvideCodeBase attribute to specify that your extra assemblies should be loaded. "Sometimes" you get lucky and it finds something else, but that's never guaranteed to work. You can see a few examples of that being used here.