Last modified on 3 February 2013, at 03:53
- Open VSH menu by clicking on the Select button from xmb(main psp menu)
- Change USB device to Flash0
- Connect your psp to pc
- Navigate to \vsh\etc\
- Open version.txt using notepad or wordpad
- In the first line change the 9.90 to 5.50 and save.
- Disconnect your psp from the pc and change the USB device back to Memory stick in vsh menu