Missing reference to Castle.ActiveRecord when compiling in Release

In debug, everything builds normally. When I try to compile in release mode, I get:

"The type or namespace name 'Castle' could not be found (are you missing a using directive or an assembly reference?)"

I obviously have the reference, or the 开发者_如何转开发project would not compile in debug either. So, what am I doing wrong?

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I had a similar problem recently (with some other assemblies). Restarting VS helped.

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I had to restart my computer in order to fix this.

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If you are using VS 2010 you have to change Target framework to .NET Framework 4, do not use .NET Framework 4 Client Profile