>Have you looked at dotnetzip yet?
>http://dotnetzip.codeplex.com/

The goal I am trying to achieve is to avoid having additiona libraries. This is why I code everything in my framework. I only want to deliver Framework.dll. That's it. That was the problem with Shell32. I had to include that in the setup and so on. The zip class I have does support also the Winzip mode. So, for now, as all the client installations has it, it was doing the job. But, I would have like to also continue to support minimum zip requirements, which I was accomplished with the Shell32 library. That one didn't require to have Winzip. It was simply using the built in Windows environment components.