| Easiest option is to power on memstick-free if it powers up fine format you memstick backing up savegames etc first, if it dont power up take the OE-A package extract the recover folder to GAME folder then copy the 1.5 update renamed from eboot.pbp to update.pbp to the recover folder and run it from recover mode by holding R at power on and select "run homebrew at... recover\eboot.pbp
__________________ Black PSP 2.71 SE-C EU 
Black PSP 3.71M33-2 EU
Black Slim PSP 3.71M33-2
Nintendo DS + M3dssimply
Nintendo Wii + Wiikey
Xbox Self Chipped, Xbox 360 NME Self Chipped
Ps3
1GB Sandisk MS Duo, 2GB Sony MS Duo, 4GB MS Pro duo, 4GB Datel Harddrive
Grand Theft Auto LCS
Grand Theft Auto VCS
3600mAh External Battery
+Plenty of Homebrew |