Ive recently just had the same problem as i was using 4.01 m33-2 on a phat psp1000 the safe way is to go through the updates instead of straight to the newest. so you start with 5.00 m33-6, this takes you to the latest M33 update
you will find this here (
File Details-CFW-5.00-M33-6-PSP - )
you also nee the offical sony update 5.00 and you will find this here (
PSP Downloads | 5.00 Firmware Update )
unzip both files and rename the offical sony update to 500.PBP then put this in the same update folder extracted from the other zip.
to install, put the update folder in PSP/GAME/ on the psp and run
There, now you have 5.00 M33-6
delete the update folder off the psp now
now you have to go from updates gen-a to gen-b to gen-b2
Gen-a Found here (
File Details-Custom-Firmware-5.50GEN-A-Build-4-PSP - )
unzip and put the UPDATE file into PSP/GAME again and run
Done
now get gen-b here and do the same as above and run(
File Details-Custom-Firmware-5.50GEN-B-PSP - )
when you have done this check your psp system information and you should see gen-b(full)
now get (
File Details-Custom-Firmware-5.50GEN-B2-PSP-Homebrew-Applications - ) and run as the same as the rest..
now you are done your system information will still say gen-b(full) still as the b2 was just a small update
THIS IS THE BEST WAY AS IVE WITNESSED A BRICKING FROM GOING STRAIGHT TO THE GEN-B2 UPDATE
most games will now work but if not follow the instructions with UMD gen and decrypter and your off......ive now got GT, fifa10, dirt2, NFS, motorstorm all going brilliantly