Short version: You don't. Longer version is it requires some very specific and careful editing of the registry which is in no way recommended, and could potentially have some unintended consequences. If you don't use this Rhino3D program any longer, you could simply remove it from your system, and the uninstaller for the program should take care of it.
So, either remove the program or just learn to live with an odd entry. You could just set 7Zip or the Windows zip archive handler to be the default choice for zip archives. Then it doesn't matter if any other programs are listed as potential programs to use, because it will default to using one of the other two programs.
Well, seems there is a issue where the file association in xp is selecting one of the two applications in my work station to open up a zip file. I have assigned 7zip as the associated application to open up zip files. The problem is, rhino3d, a old 3d application, is in the list of recommended applications to open up a zip file, and I have no way to remove it from the list.
To better understand the steps to get to this window, goto start > my computer > tools > folder options > files types > scroll list down to zip file > change > open with window. In the open with, the recommended apps to open up the zip file are rhino, 7zip, and xp native zip application. Where to I take out rhino3d 3d application in the recommendation list?

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