Help ! - Windows XP, minimized windows buttons have disappeared !

[#1]

I have an old PC running Windows XP home edition.
It is fully patched with all the latest updates for Windows and other installed applications.
With the exception of this particular problem it works perfectly.
The problem is that when any running application window is minimized, no minimized button appears on the task bar, so I have to ALT-TAB to maximize any hidden windows. 
The quick launch icons on the left side of the task bar, and the start-up application icons on the right hand side work just fine, it is just the minimized window buttons in the middle that are missing !. 
The machine does NOT have a virus, or other malware, and the problem first appeared following a restart after a power cut  which was doubly annoying as the UPS battery on that machine failed at that same moment ! 
I don't know -
1) Whether I have lost the taskbar that the minimized buttons appear on.
2) Whether the taskbar is present but, hidden, located outside the screen area, or underneath another taskbar, etc.
3) Whether the taskbar is OK, but the mechanism for putting minimized Window buttons has failed.
Any ideas ? - I have checked the Microsoft help pages, and Googled for ideas - but I have not found anything useful yet ! 

[#2]

Probably too late now, but it's always safest to run System Restore after an unexpected shutdown.

[#3]

I tried that but without success. 
I have never had much luck using System Restore, it fails to restore when it is most needed, but works when I am just testing it !

[#4]

Dunno if this'll work, but try going to:
http://www.kellys-korner-xp.com/xp_abc.htm,
clicking on 'T' in the top bar, then download and run "Minimized Programs Missing".
(Might be an idea to create another System Restore point first).
HTH

[#5]

Thanks for that possible lead !.
I will have to look at that in some detail, as I am a little wary of blindly running .vbs files downloaded from the internet.
I will see if I can work out what the script does, and see if the site can be trusted.
Thanks again.

[#6]

Quote from: purleigh

I have never had much luck using System Restore, it fails to restore when it is most needed, but works when I am just testing it !

Possibly you are running security software that blocks System Restore?  Both Norton and Kaspersky will do this if you don't adjust their settings, though not necessarily if the restore point is sufficiently recent, which might explain why it has worked in tests.  If you cannot get System Restore to work I would regard that as a more serious problem than the lack of minimized window buttons.  Have you tried running System Restore from Safe Mode?  That should defeat Norton or Kaspersky's attempts to block it, though they will complain bitterly afterwards.