Paste does not work in Command Window

All,
Paste suddenly seems to have stopped working in the Command window in
my Vista system.
Configuration: Vista enterprise with SP1. UAC ON (I cannot disable
UAC because of corporate IT policy)
I am sure "Quick Edit" is enabled. I tried both "Right Click" and the
menu Edit -> Paste
option. It does not work even in Powershell. Paste works normally in
all other applications.

Paste also works fine if I copy from the same Command Window or even
from any other command window.
But I if try to copy from, say Notepad or Word, and try to paste on
any Command Prompt, nothing happens.
I can copy FROM any Command Prompt to any other application

I tried on normal as well as elevated (Admin) Command Prompts. Same
result. Does not work :-(

It used to work fine till about a month ago. I do not recollect any
major change that could have
caused this problem. Any clues?


Thanks in advance for any help!

-Regards,
Venkat