The PostSharp Assembly is added when you your “paket.references” file in the project directory containing just one line “PostSharp”. If you execute “paket install” in your command promt, paket adds PostSharp as reference to the project and modifies the csproj accordingly.
The next time you run a build, PostSharp comes up with this dialog:
Since the VisualStudio PostSharp plugin detects a reference to PostSharp.dll, it expects a packages.config which it can’t find. If you don’t agree, the solution builds successfully but the code won’t be modified by PostSharp.
I posted this on Twitter. The Paket maintainers can’t handle this and PostSharp won’t change this behaviour.
So by now, I don’t see any solution except that Paket users can ask PostSharp to change this behaviour.
//Edit: Have a look at the comments. The unsolved problem is that you have to execute the „install.ps1“. Paket doesn’t do that but NuGet will also remove this feature in a future release.