Sadly, nothing ENFORCES that an added program be listed in the Add/Remove list. Some new users don't notice the scroll bar on the list either.
If you add a program that doesn't list in the Add/Remove tool, see if they provided an uninstaller or if push comes to shove, you can use a manual method of deleting it's program directory and it's shortcuts.
The more advanced user will use a tool like the formerly freeware JV16 powertools kit noted at http://www.321download.com/LastFreeware/ to delete the programs litter in the registry.
Bob
I am new to XP Home, Dell Dimension 4600. Everything running reasonably well, but...when I go into add/remove programs, it just lists a few programs. If I change the sort, it lists different programs. I did manage to uninstall one today. The date last used is incorrect (on the ones it shows). This is bad because I've been trying out some programs (photo) and need to uninstall.

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