Originally posted by dakilla010
its not modded its straight from the sever it a clean update
You need the newest PayLoad of PSGroove. This payload allows you to install retail package files along with homebrew ones.
If you flashed/install PSGroove yourself, look for an update for your device. If you bought a jailbreak device, then try to look for an update on the site. If there isn't any updates you're stuck.
If you're trying to install a clean MW2 patch, turn your PS3 on without the Jailbreak running and make sure you're connected to the internet; when you start up MW2, you should be prompt for a patch update. Just install it, and quit the game directly after installing, and run your jailbreak again.
Hope it helps.