Within the past few weeks, I bought a used PSP 1000 cheap and have updated the firmware via a wireless connection. My system firmware version is list as 5.01, but if I try to go to the Playstation Store to download something, it states that a system software update for the PSP system is required. If I try to update the firmware, it states that there are none available. Any idea what is going on?

Thanks for any help someone may be able to offer.