control panel icons and other shell folders quasi-disabled

[Tait]

On a malware-infested computer, the control panel opens, and all the icons
are present, but after double-clicking most of the icons, nothing happens.
Some work -- like network connections, and task bar properties, but most --
add/remove programs, user accounts management, system -- don't. Invoking
appwiz.cpl, nusrmgr.cpl and so forth from a command prompt opens the applets
just fine. I've run into this behavior repeatedly on many different
malware-infested computers and have yet to find a solution short of reloading
Windows. Has anyone else seen this behavior? Anyone have a solution?

I know the ideal solution is to reload. I'm really only interested
specifically in a solution to or cause of this particular problem. Anyone?

Thanks.