Best Answer Cytrick, 18 May 2020 - 18:59
Le contenu de son readme.txt pour info :
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Updating 3.40 OE-A to Most recent OFW/CFW. ```
MAKE SURE TO HAVE 80% BATTERY+ AND CHARGER PLUGGED IN FOR WHOLE PROCESS. ENSURE THERE IS 100mb+ AVAILABLE ON MEMORYSTICK. ```
1. Put 3.52M33-1 M33Creator folder (just the folder M33Creator with its contents) into the GAME150 (:/PSP/GAME150) folder on your PSP. It contains 1.50 and 3.52 updates to create your cfw file..Make the GAME150 folder if it is not there. . .
Exit usb mode, run M33 CREATOR on your PSP. Process takes 15mins to make your cfw file. Follow onscreen instructions. Once finished go back to XMB and there should be 3.52M33 UPDATE. Launch it and follow instructions. It will then update you to 3.52M33-1 CFW.
2. Once updated, copy folder M33UPDATE4 from the 3.52M33-4 folder and place it into GAME150 folder on the PSP. Launch the updater. Follow onscreen instructions. Check system settings->system information to check you are now on 3.52M33-4.
3. UPDATE FROM 3.52M33-4 to 3.71M33:
- Copy the UPDATE (3.71M33 folder) directory into /PSP/GAME/UPDATE and copy the EBOOT.PBP of the 3.71 Sony updater
there but with name "371.PBP". Note: the program will not even show if you copy it to a different folder than that.
- If you are in the fat psp, make sure you have configured the psp to run the game folder in the 3.XX kernel. (THIS MEANS PRESSING SELECT ON THE XMB, OPEN RECOVERY MENU, AND MAKE SURE THE GAME FOLDER/KERNAL MODE IS 3.xx NOT 1.50)
- Execute the program, it requires 78% of battery. If you have idstorage corrupted due to a downgrader, the program
will ask you to correct it automatically so the update can continue.
- Press X, and the Sony updater will begin. Sit and enjoy while Sony code installs 3.71 M33 
- When finished, the updater will ask you to reboot (pressing X or O). DO IT. Do not skip this step
shutting down the psp by yourself, or you'll end with a brick.
- You should be now in 3.71 M33
4. You should now be on 3.71M33 CFW. Go to the sony website for the latest official firmware. Install it through the XMB software update option.
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