Message "For testing purposes only" just appeared

[slashandburn]

the message "For testing purposes only" just appeared on my desktop. How do i get rid of it? It just appeared after i was messing with my registry and windows media player.

[Codename_Falcon]

I received this message after installing the testing version of Service Pack 3 on Windows 2000. I found that deleting the following key in the registry got rid of it.
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SystemCertif icates\Root\Certificates\2BD63D28D7BCD0E251195AEB5 19243C13142EBC3]