Things You'll Need
Instructions
Turn the PSP off and remove the battery and memory stick from the PSP. Insert the Magic Memory Stick and Pandora battery in that order, into the PSP. It will turn on automatically.
Press the "X" button two times to re-flash the firmware to your PSP. This will clean up all the corrupted files that are preventing the PSP from working. Press the "X" button once more when the process completes. This will shutdown the PSP.
Remove the Magic Memory Stick and Pandora battery. That part of the job is now finished. Reinsert the normal battery and memory stick into the PSP and turn the PSP back on. Connect the charger to the PSP.
Select "System Update" from the PSP main menu. This will update the PSP to the most recent Sony firmware update. As the PSP has now been reset, It is free to update the firmware. The PSP will reboot on its own. When it powers back on, the PSP will be working as good as new.