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?

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

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

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