Can't copy-n-paste

[LRW]

I have a feeling this problem is very closely related to my earlier post:
"Corrupted file explorer icons."

I have WindowsXP Pro which I recently reinstalled after a clean format.
Since then, I can't copy-n-paste. I try using CTRL+C and CTRL+P, CTRL+Insert
and Shift+Insert, right mouse "Copy" and "Paste", and Edit dropdown "Copy"
and "Paste". But in each and every case nothing happens. No matter what
application: Windows native such as Word Pad or any 3rd party application.
Although CUT works...be it CTRL+X or Edit dropdown "Cut". (Although Paste
doesn't work with that either.)

Any ideas? Based on the other thread, here's what I've done already:
Start --> Run: sfc /scannow

Any ideas?
Thanks!!
Liam