Why I have to delete `bin` folder of my project before each build?
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I am working on a C# application which I ahev devided it to few projects. Recently when the soloution becomes larger, I get different errors such as `MissingMethodException` or even worse, DLL not found messages.

The only soloution is to delete my bin folder and build the project again.

I wonder if this is a common problem with visual studio or might be I am doing something wrong?