I've written this tut becuse of many peple asking how to return to there origional 1.5 firmware.
If you are using the proof of concept firmware by Dark_Alex and didnt brick your psp you should use this tool by Slasher at POC Custom Firmware - Unflasher
If you have bricked your psp via boot screens,wallpapers,bootso unds,font or any other means [exept anything that damages that affect crusial prx's]
1.Download This File Clicky
2.Boot you psp with the poc firmware on it holding the Right Sholder button
4.Place the file in the root of your memory stick and you 1.5 update file in a folder named update in your game directory
5.The press triangle folowed by cross
And your back at 1.5.