Downgrading Custom Firmware (OE / M33)

Note: This guide is for use with regular PSP units only, the following steps are not to be performed on a PSP Slim.

Want to go back to a previous OE revision or have decided that custom firmware is not for you? Here is how to downgrade your new custom firmware installation in five easy steps.

Recovery ZIP for Custom Firmware 2.71 - 3.52
Recovery ZIP for Custom Firmware 3.71

It's important that you download the recovery ZIP corresponding to your firmware version.

• Extract the Recovery ZIP.
• Place the "RECOVERY" or "UPDATE" folder in X:/PSP/GAME/
• Download the 1.5 Update, save as file name "UPDATE.PBP"
• Move "UPDATE.PBP" into the same folder you placed on your memory stick in Step 1.
  
  If you are running custom firmware 2.71 - 3.52
• Everything is setup! Hold R while turning on your PSP to enter recovery mode, and choose the option which reads "Run program at.." to begin downgrading to firmware 1.5.
  
  If you are running custom firmware 3.71
• Navigate to the Game menu and launch "Update to X.Y.Z." You may be asked to patch your idstorage keys, if so, press X.

Thanks Guys

Now i have best of both worlds!!!!!!!!!

You can also just run a different oe update and it will work fine. You can't run the 1.50 update though.

Can you do the same thing on the normal sony 3.30?

themlody said:

Can you do the same thing on the normal sony 3.30?

Click to expand...

not really. No downgrader T'ill this day has been found for that version yet

Thanks, but how comes when i went it my games folder it said Corrupted Data please help me.

Ichigo04291982 said:

Thanks, but how comes when i went it my games folder it said Corrupted Data please help me.

Click to expand...

erm, your not supposed to run it from the PSP game menu. You have to run it from recovery..

I have 3.40OE and want to go back to 3.10OE...

how to do that???

Need to go to 1.50 and then to 3.10oe, or just do the normal instalation of 3.10oe on my 3.40OE PSP??

regards
PN

pnunes said:

I have 3.40OE and want to go back to 3.10OE...

how to do that???

Need to go to 1.50 and then to 3.10oe, or just do the normal instalation of 3.10oe on my 3.40OE PSP??

regards
PN

Click to expand...

just run the normal installation over it

WTH

Ok, I have always used the method presented in the first post, but one of my friends (he had 3.03 OE) simply created a folder RECOVERY in PSP/GAME and put 1.50 update (named as EBOOT.PBP) and run the recovery from the recovery mod, and it worked. I am totally confused?! How the hell is that possible?

btw when PSP booted in 1.50 it just said "Contact sony computer entertainment technical support line for assistance", and simply entered XMB.

Now my question is, how is that on earth possible to do without the files provided in Flasher for recovery folder?

ryo-n-gats said:

Ok, I have always used the method presented in the first post, but one of my friends (he had 3.03 OE) simply created a folder RECOVERY in PSP/GAME and put 1.50 update (named as EBOOT.PBP) and run the recovery from the recovery mod, and it worked. I am totally confused?! How the hell is that possible?

btw when PSP booted in 1.50 it just said "Contact sony computer entertainment technical support line for assistance", and simply entered XMB.

Now my question is, how is that on earth possible to do without the files provided in Flasher for recovery folder?

Click to expand...

well it might be possible on 3.03 OE (can't remember) but it definitely doesn't work on any recent OE revisions.

anyways the recovery folder is a better solution since people who are recovering from bad XMB or font flashes wouldn't be able to run the Sony updater as it loads vsh modules.

x3sphere said:

well it might be possible on 3.03 OE (can't remember) but it definitely doesn't work on any recent OE revisions.

Click to expand...

Ok, thanks for clearing that up for me.

anyways the recovery folder is a better solution since people who are recovering from bad XMB or font flashes wouldn't be able to run the Sony updater as it loads vsh modules.

Click to expand...

One thing more, does it mean that people have already tried to downgrade OE to 1.50 without standarad procedure? (because i saw it first and only time when my friend did it, I'm just interested did somebody suceed too)

ryo-n-gats said:

Ok, thanks for clearing that up for me.

One thing more, does it mean that people have already tried to downgrade OE to 1.50 without standarad procedure? (because i saw it first and only time when my friend did it, I'm just interested did somebody suceed too)

Click to expand...

nah, this is the first time I've heard of someone just using the official Sony eboot. although I'm sure others have tried it.

not working

i want to go back from 3.40OE-A to 1.50 and i did what that they said and the psp turned off.
and when i want to play games, the psp is loading and then shutting down...
what can i do?!?!
please help me!:sad:

avivp12 said:

i want to go back from 3.40OE-A to 1.50 and i did what that they said and the psp turned off.
and when i want to play games, the psp is loading and then shutting down...
what can i do?!?!
please help me!:sad:

Click to expand...

what's in your recovery folder?

it should contain these files..

decryptprx.prx
EBOOT.PBP
extprxs.pbp
libpsardumper.prx
UPDATE.PBP

problem

dude look some of the games working and some of them do working, and i want to stay on this fw.
now why does some of the games like Burnout Dominator and others aren't working?

problem

now dude i want to downgrade back to 1.50 can you send me a link file for those files?

Heres the recovery files here just put the 1.50 update in it and rename it to UPDATE.pbp then put it in the GAME folder then run them from recovery mode.

ok thanx, and now another quastion, why does games sometimes dont work?

avivp12 said:

ok thanx, and now another quastion, why does games sometimes dont work?

Click to expand...

have you tried disabling NO-UMD in recovery mode? also this isn't really the proper place to ask this.. should've made a thread in the help center.