Auto hide function for taskbar becomes inoperable and resetting the chick box will not repair it.
Windows 7 Home Premium
Compaq CQ5210Y
Three user accounts on PC
Dragging short cuts to desk top causing problems. Doing this created duplicate icons on taskbar. Correcting the problem by deleting them from taskbar removes them from all programs section. In some situations they can not be removed at all.
Solution: Remove problematic user account and create a new one, well for now at least. (Also had a software hang when removing the problem account.)
Might be data corruption on a two week old PC.
This is FYI. This thread untracked

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