Well, the only thing you can do now is to use Pandora Battery and Magic Memory Stick to help you downgrade.
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1. First boot up the PSP into recovery mode (hold R during boot) and make sure the GAME folder homebrew setting is set to 3.X Kernel. Exit recovery mode.
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hmm.. i got a problem here,i cant boot my PSP holding R. id tried that once,but stil i cant boot up my psp
. can i ask something?(sorry for being noob). what does 'set to 3.X kernel' mean??