
If that doesn't work, then you'll probably need to find a way to remove all traces of whatever you had on your PSP as far as custom firmware goes. I'll already tried updating it via Wi-Fi, same problem. Please follow the instructions on this page from Sony on how to update your PSP via computer.

Web Archive – PlayStation Support – PSP System Update Please notice the folder names and folder layout presented on that page.

Place the EBOOT file in a folder named UPDATE in /PSP/GAME/ on the PSP memory card or internal memory if you are using a PSP Go. Disconnect from USB mode and view your games list.
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Launch it and follow the directions to update to 6.60 or 6.61 firmware. HOW TO UPDATE PSP FIRMWARE 6.60 INSTALL.
