Caution! – This may brick your PSP if the steps are not followed properly! Please follow all of the instructions carefully, and if it doesn’t work and you brick your PSP, I didnt twist your arm, or hold a gun to your head, so don’t come crying to me.
Step 1:
You will first have to upgrade to 3.02 OE-A then to OE-B before you upgrade to 3.03 OE-B. So the first thing you have to do is download 1 of the following files:
For 1.50 firmware download 3.02 Basic Installer for 1.50
For 2.71SE firmware download 3.02 Basic Installer for 2.71SE
You will not need both files, so download 1 of them. Once you have the installer downloaded to your computer, plug your PSP in and activate USB file transfer mode.
*NOTE* I backed up and formatted my memory card before installing the firmware updates, you may want to do this aswell. You will also have to have atleast 75% of the battery remaining or you will not be able to upgrade.
After activating USB file transfer mode, run the installer, choose the drive your PSP is setup as, and hit next. The installer will do everything for you. You may notice the installer stop at 37%, but let it copy all files, so sit back and relax. Once all the files are copied, exit USB file transfer mode, goto the game menu, access the memory card and you will see the Launcher for the 3.02 updater. Execute this.
You will have to agree to the agreement, do this by pressing X and the update will now start. Once the update is running DO NOT turn off your PSP, or remove the memory card! When the update is complete, it will advise you to restart your PSP manually, you can now do so.
When you restart your PSP you will get a message saying the configuration is corrupt and has to be rebuilt, dont worry, press O and re-configure your PSP.
Congratulations you have no updated too 3.02 OE-A!
Step 2:
You will now have to upgrade 3.02 OE-A to 3.02 OE-B, which is easy, just download oeb.rar which is the upgrade file. Again, reactivate USB file transfer mode on your PSP and extract the contents of oeb.rar to GAMEGAME150 on your PSP memory stick.
*NOTE* You may have to create the GAME150 folder in the GAME folder.
Once everything is copied, run the updater from the Game menu on your PSP.
Easy enough, you are now upgraded to 3.02 OE-B!
Step 3:
Now to actually upgrade to 3.03 OE-A.
First you will have to download 3.03OE-A.rar Once the files are downloaded, initiate USB File Transfer mode on your PSP and extract 3.03OE-A.rar to GAME150 in the GAME folder on your memory stick. Once all the files are copied, close down the USB File Transfer Mode, and goto the Game Menu, and run the 3.03 OE-A Updater.
Again, you will have to agree to the agreement by pressing X and the update will now start. Once the update is running DO NOT turn off your PSP, or remove the memory card! When the update is complete, it will advise you to restart your PSP manually, you can now do so.
This time I didnt receive an error stating that anything was corrupt, and everything booted up just fine.
You are now running firmware 3.03 OE-A!
Step 4:
Now you are good to update to 3.03 OE-B. Download OEB_UPDATE.RAR. Once the files are downloaded, once again initiate USB File Transfer mode, and uncompress the contents of MS_ROOT to the root folder of your PSP.
Once this is complete, exit USB File Transfer mode, and execute the 3.03 OE-B updater from the Game menu. As soon as this is complete you will be fully updated to the 3.03 OE-B Firmware. You can confirm this by going to the settings menu on your PSP and looking inside of the System Information menu.
Step 5: (Optional)
You may want to now format your memory stick again before copying any of your old files back. If you do this step, you must then initiate USB File Transfer mode once more, then go into the GAME folder, and create GAME271 and GAME150.
All of your old homebrew software can now be placed inside of the GAME150 folder and will still run. Ultimately GAME271 is for stuff that runs on the 2.71 firmware.
If you have any questions/concerns or comments. Feel free to comment below!