This is not a Mind Altering tweak but One Which Eased an Itch.
Nor is it copied -but painfully thru experimentation&advice.
Hopefully someone has a simpler solution.
LOOK HERE: RightClick Start button\Properties\Taskbar\(mark hideinactive)\Customize\Past Items
The list in Past Items contains programs uninstalled a long time ago.
I tend to un\install alot of software & Registryclean etc. after uninstalling.
The list still grows
Open Regedit (start button-run-type: regedit -ok)
The right page says
IconsStreams REG_BINARY 14 00 00......
PastIconStream REG_BINARY 14 00 00......
Delete Both lines (rightclick to delete) - Close regedit
Open TaskManager (press Ctrl-Alt-Del) - Processes - rightclick Explorer.exe - End Process -Yes
File - New Task
Now Check (startbutton\properties\taskbar\customize\past items)
It is Clean.
Once you start using different programs again- they will turn up
and build up again...
Windows has a lot to fix.........