Only for custom Firmware that can access the recovery menu.(noob guide)Reflashes back to 3.03oec
1. Turn your psp complety off by holding the power button up for 4seconds
2. Enter the recovery menu by while switching on holding r1(right hand trigger)
3. Toggle the usb by selecting "Toggle Usb"
Picture3. Download and run this installer file
Download4. Disable usb mode and select "Run program at /PSP/GAME/RECOVERY/EBOOT.PBP"
5. Now it will start the reflash eboot.
6. Hit X at the menu that it ask and use this at your own risk.
7. Hopfully it will work fine and you will be back on the road.
Ps xflash will semi brick your psp if you try to spoof the 13.99 or 9.99 so dont.