Removing Shell Extension so I can re-install to fix it

Still trying to fix my thumbnails and file previews. What happened after I uninstalled X6 was that the file preview (the one in the preview pane that shows all the pages of the file) went away, just get a message "No preview available". I posted about this in another thread a while ago and didn't have much luck. So, I'm back at this now that I have time and I'm trying all the suggested options. One thing was to uninstall the shell extension and reinstall. Well, tried that and the X6 shell extension goes away nicely but the X5 shell extension will not uninstall. It pops up the dialog asking if I want to uninstall then does nothing. I can't re-install if it won't let me get rid of the version that's already in there.

Running win 7, and have already tried doing a repair install of X5 and re-installed the SP3 patch, still no help. I get most of the file thumbnails, but not all of them, and no preview pane.

What I'm looking for is a "force uninstall" or a program that will clean out the shell extension files & registry so that I can start fresh. Any ideas?