Windows XP permissions messed up (???)

WinXP Pro SP3 - here's the deal... the PC boots fine to the login screen where we have "user 1" and "user 2". Both user accounts have the same problem. When I try to run ANY program, it doesn't run unless I right-click and select "Run as" and then click OK. I do not have to change anything in the "Run as" window. If I simply double-left-click on a desktop short (or try to run something via Start > All Programs), nothing happens. No error, nothing. Here's something a bit weird: lets say I try to run MalwareBytes by double-left-clicking the desktop icon, nothing happens; then I right-click on CCleaner and select "Run as" and then click "OK" in the "Run as" window and CCleaner opens just fine, but the MalwareBytes icon on the desktop remains a faded blue as if it's still selected or highlighted. Strange. Anyway- I have tried numerous "permission fixer" utilities w/o any positive results. I've poked around here and there but I'm not even sure what I'm looking for. The client said he was in "Add/Remove Programs" and says that "I must have removed the wrong thing to cause this kind of BS" and I'm thinking this type of BS cannot be cause by uninstalling something thru "Add/Remove Programs". Time is important on this so if anyone has any info, PLEASE post it kind of soon....

HUGE THANKS!!! (as always)

-DLB-

 

NOTE - Internet Explorer 8 opens fine on both user accts without having to use right-click-run-as-OK.... strange....

 

This is kind of a long shot but what happens if you download the LNK registry fix here. Or you could go for the nuclear option. Batch file association fix.

http://www.dougknox.com/xp/file_assoc.htm

 

I already tried the all purpose file association fix batch file and it did nothing.... I don't think it's a file assoc problem because everything runs fine if I right-click > Run as > OK.

Also, both users are admins but when I try to install software it says "you must be logged in as an administrator to continue" which clearly points to a permission problem.

 

2 really left field ideas dlb.

1) In Add/Remove, may he possibly have been in the Windows Components/Features and turned something off.
2) Was he in Services maybe and turned something to manual/disabled.

 

Have you tried using d7 for repairing permissions? It's under Misc in the repair tab.

http://majorgeeks.com/D7_d6954.html

UVK will also reset registry and file permissions. Under system repair.

http://majorgeeks.com/UVK_Ultra_Virus_Killer_d7653.html

If you create a new user account, does the same thing happen?

 

Thanks for the suggestions.... I have already tried this and this and this and a couple of other tools from the folks at Tweaking.com and so far nothing has worked. I'm in mid repair install now . . . fingers crossed!

 

The repair install seems to have worked! Thanks for input everyone!