How to Downgrade Sony PSP firmware from 2.00 to 1.50

By: Sony PSP Fan

Hi,

Today, I will give you step-by-step to downgrade your Sony PSP firmware from 2.00 to 1.50. Before starting, you must have 2 files downloaded from internet. They are MPHDowngrader.zip and E_BOOT1.5.zip. (You can see link at the end for downloading.)

Let's see the step in detail

1. Unzip the files MPHDowngrader.zip and EBOOT_1.50.zip.

2. Connect your PSP to your PC via USB connection.

3. Open up Window Explorer and go to Removable disk which is your Sony PSP

4. When you open Removable disk, you should be at Root directory of your Memory Stick. Then, you copy Index.dat and h.bin to your Sony PSP's root directory.

5. Go to PSP\PHOTO folder (for example G:\PSP\PHOTO\) and copy overflow.tif to your Photo directory.

6. Then, go to PSP\GAME and check whether folder UPDATE exists or not. If folder UPDATE does not exist, you must create this folder under PSP\GAME. Then, you will get G:\PSP\GAME\UPDATE.

7. Copy file EBOOT.PBP into PSP\GAME\UPDATE folder.

8. Let's check again that you have those files in the specified folders.

• X:/h.bin
• X:/index.dat
• X:/PSP/PHOTO/overflow.tif (with no other pictures in there)
• X:/PSP/GAME/UPDATE/EBOOT.PBP (the 1.50 Firmware update eboot)

9. Next, disconnect your USB connection and plug AC adapter to your Sony PSP to make sure that your Sony PSP will have enough power during downgrading firmware.

10. On your Sony PSP, navigate to PSP\PHOTO folder and scroll to overflow.tif. You do NOT have to do anything. Everything will start automatically. Now, you will see strange texts display on your screen. Don't worry, everything is fine. This will take about 30 seconds. Then, restart your Sony PSP. Hold the power button up as long as it takes to fully shut down your Sony PSP, it will take much longer than usual.

11. When your Sony PSP becomes available again, then on PSP menu go to GAME icon and scroll down to memory stick. Select it and you should see the 1.5 update. During updating process, do NOT interrupt it in anyway.

12. The update process should not take very long time to wait. When the process complete, you will see the error at 99% completion. Don't panic, this is normal. Let's restart your Sony PSP again by pressing Power until it completely shutdown.

13. Now, turn your Sony PSP back on. You will see another error. Just press the "O" button and it will restart after rebuilding the system data. Then just set it up as you did when you first got your PSP and you have a brand new firmware 1.5 Sony PSP. Be responsible with it. Once complete, you can remove the downgrader related files from the memorystick.

Above are the complete steps to downgrade Sony PSP firmware from 2.00 to 1.50. Please read and understand the step clearly before making any progress. Enjoy your Sony PSP firmware 1.50.

Link: http://forums.qj.net/showthread.php?p=177883#post177883.