Zip And Unzip A File In VB 2010?

I am trying to find out how to zip and unzip a file in Visual Basic 2010. I have looked extensively on google and youtube, but found little of use. I was able to run one block of code though:

Sub CompressFile(ByVal filetozip As String, ByVal zipfile As String)
Try
Dim fs As FileStream

[Code]....

but this is not what I need. I am creating a Desktop Screen Capture Program, for personal use, that takes a screen when a set timer ticks (1 min or 60000 milliseconds) and in that timer tick a call to a sub is made, CompressFile( file, compressedfilename). See the problem here? It overwrites the compressed file with the second screenshot. So I need to know how to create a Zip Archive, preferably Not using Gzipstream. I need one that i can open in Winzip or 7-zip. And before you ask, yes I tried to add a reference to the 7z.dll, and error. It does not matter whether the solution to this problem requires outside or inside visual basic, though i ask you ensure it is Virus-Free if it involves downloading.