From Firmware 3.03:
Downgrade from 3.03 to 1.50
You will need the orinal game GTA Liberty cities v2.0 (old game, new version is 2.6 and it doesn’t work) or Lumines Game (brand new exploit, so I’ll explain the other one just in case)
Install Custom Firmware 3.4 oe-a
You need to use an unpatched UMD copy of "Grand Theft Auto - Liberty City Stories" to do the downgrade.
This downgrader only works with an Unpatched "Grand Theft Auto: Liberty City Stories" UMD.
Unpatched UMDs will have the Firmware 2.00 update on it, UMDs with the 2.60 firmware update will not work.
Finding an unpatched copy of Grand Theft Auto - Liberty City Stories:
•Try looking in a local shop that rents or sells used PSP games
•Do a search on e-bay or another similar website...
•Try to borrow a copy from your local library...
How to tell if its the correct version without inserting the UMD into your PSP
The game box will have the correct serial even if the game is patched, you can't use the box to tell if its unpatched.
Required Files:
IdStorage Corruption-Free 3.03 to 1.50 Downgrader:
Download : http://www.zshare.net/download/corruption-free-3-03-to-1-50-downgrader-rar.html
This is the latest 'IdStorage Corruption Free' downgrader,
you won't need to repair your IdStorage after using the downgrader.
Downgrading Instructions:
Before you start, you need to make sure that 'UMD Auto-Start' is turned "off" in the 'Settings' -> 'System Settings' menu.
1. Transfer any important data from your memory stick to your computer and then
format the memory stick using your PSP, its in the 'Settings -> System settings' menu.
Note: Formatting will erase all data from the memory stick.
2. Connect your PSP to your computer using a USB cable and make a USB Connection.
3. Right click the RAR file you downloaded earlier and choose 'Extract files...' from the menu and a new window will open.
If you don't have 'extract files...' on the menu then you don't have winrar installed. (Download link at the very top of this topic)
Select My Computer and then slect the drive letter of your PSP and click "extract"
(My PSP memory stick drive letter is Removeable Disk (E:) but it might be a different letter on your computer)
Winrar will then unpack the files to your PSP Memory stick, this may take a minute or so.
Once its finished unpacking the files, Double click the 'Safely Remove Hardware' icon near the clock
Select the 'Sony PSP USB Device' and click 'stop', on the next window click 'Sony PSP USB Device' and click 'OK'
You should get the message 'This device can be safely removed from your computer', Click OK to this message.
4. Close the USB connection on your PSP (press 'O') and unplug the USB cable from your computer and your PSP.
5. Insert the unpatched copy of "Grand Theft Auto : Liberty City Stories" into your PSP.
6. Go to the game menu and start the UMD.
7. It should get to loading savegame then the screen will clear to black and fill with a light blue colour.
After this the PSP will reset itself, once you are back in the XMB remove the UMD.
If this does not happen make sure that you have the unpatched verson "Grand Theft Auto : Liberty City Stories"
It should have a 2.00 firmware update on the UMD. If it does not then it is a later version and can not be used to downgrade.
If your PSP turns itself off / freezes, Turn off your PSP by holding the power button for 4 seconds.
turn on your WLAN switch (the switch on the left of your PSP should be 'up'), turn your PSP back on and run the game again.
8. Check that HEN is running by going to system settings, then to "System Information".
If your System Version is '3.03 HEN' then HEN is loaded, proceed to step 9.
9. Go to the memory stick and run the "Update X.YZ" program.
10. If you have an unpatched TA-082 or higher motherboard you will be prompted to patch your PSP so it can be safely downgraded.
The downgrader will not let you proceed without patching, if your motherboard requires it.,
11. Before the downgrader starts, you need to agree with what it is going to do.
If you no longer want to downgrade, press the "R" (Right Shoulder) button.
If you agree to start the downgrade press the "X" button.
Warning: Do not unplug the PSP or try and restart it yourself, doing so will brick your PSP.
12. When the downgrade has finished the PSP, you will need to press X to restart your PSP.
13. If you get a blue screen error saying the settings are corrupt then press O to restore the default settings.
(You will need to re-enter all the settings into your PSP again, like time / date / network settings etc...)
14. Format your memory stick and then you are all done. You should have a Firmware 1.50 PSP
That was the hard part. To install 3.4 OE-A from v1.5 download this file: http://www.zshare.net/download/custom-firmware-3-40-oe-a-installer-rar.html
Unrar the file and place the two folders inside the game folder (340oeflasher, and 340oeflasher%) inside the PSP game folder. Disconnect from the computer and run the exploit like if it was a game. Follow the prompts carefully and done.
One more thing. Format your memory card from the psp menus after installing 1.5 and after installing 3.4
Best way to find torrent downloads is to use yahoo or google and type name+torrent+psp. Once you find a good site keep it and use it again. Example:
(shrek 3 torrent psp) /search
Install a torrent software first. Some are better than others. Try utorrent. Search like this for it: (utorrent download)/ search