Downgrade your PSP to any 6.xx OFW

If you have updated your PSP to 6.38 OFW or 6.37 OFW or even the latest PSP firmware, 6.60 OFW and found yourself without a Hen or CFW that’ll allow you to run homebrew or free PSP games well you’re in luck!
PSP developer some1 (yes, that’s his handlename, don’t ask why) has released a Signed downgrader that will allow you to downgrade your PSP from 6.38 to 6.20. While it is a port of Davee’s original downgrade for 6.3x to 6.20, some1 managed to make it work for 6.38 OFW, the current latest firmware available for the PSP. It should, in theory, still work for downgrading 6.35/6.31 to 6.21 but some1 says he hasn’t tested it so try at your own risk.
Update: updated to v4 of some1′s downgrader which now supports 6.60 OFW
Important: Some PSP’s can’t be downgraded beyond 6.3xx, spefically0 8g and 09g models.
Important update: some1′s downgrader officially supports:

• Downgrade from 6.60 OFW to 6.60 OFW, 6.39 OFW, 6.38 OFW, 6.35 OFW, 6.31 OFW or 6.20 OFW
• Downgrade from 6.39 OFW to 6.39 OFW, 6.38 OFW, 6.35 OFW, 6.31 OFW or 6.20 OFW
• Downgrade from 6.38 OFW to 6.38 OFW, 6.35 OFW, 6.31 OFW or 6.20 OFW
• Downgrade from 6.35 OFW to 6.35 OFW, 6.31 OFW or 6.20 OFW
• Downgrade from 6.31 OFW to 6.31 OFW or 6.20 OFW
• Downgrade from 6.31 OFW to 6.20 OFW

Requirements

• A PSP with any of the following firmwares installed:
  • 6.60 OFW
  • 6.39 OFW
  • 6.38 OFW
  • 6.35 OFW
  • 6.31 OFW
• Download: 6.3x Downgrader v4
• Download the OFW version that you want to downgrade to:
  • 6.39 OFW:
    • PSP-1000
    • PSP-2000
    • PSP-3000
    • PSP Go
  • 6.35 OFW:
    • PSP-1000
    • PSP-2000
    • PSP-3000
    • PSP Go
  • 6.20 OFW:
    • PSP-1000
    • PSP-2000
    • PSP-3000
    • PSP Go

How to Downgrader on your 6.xx PSP

Important Note: If you chose to downgrade to 6.20, you will get a BSOD (saying that your system information is corrupted), this is OK, just click circle to reset your system information and you will be back to normal.

• Extract the OFW zip file on your PSP
• Copy the resulting folder to x:\PSP\GAME\UPDATE (x is your memory stick or the PSP Go‘s storage)
• Extract the 6.xx Downgrader v4.zip file on your PSP
• Copy the 6.xx Downgrader v4 folder into PSP/GAME/
• Run the downgrader from the XMB
• Follow the instructions and then wait for it to boot the OFW Update
• When PSP Reboots press O to reset settings
• Congratulations, you have successfully downgraded your PSP.

If you’re wondering what to do after downgrading, you can install the latest pro LCFW build like 6.20 Pro-B8, 6.35 Pro-B8 or 6.39 Pro-B8.