Official Firmware Update: 6.39
Sony Playstation has released their newest firmware 6.39. It has improved system stability.
Nothing more than a “fix”. The downgrader kxploit is closed!
Obviously not, some1 has modified his Downgrader and it is now working with firmware 6.39. For more info, check the original article here.
1. Download the 6.39 UPDATE.
2. Create UPDATE folder in ms0/PSP/GAME
3. Copy the EBOOT.PBP in ms0/PSP/GAME/UPDATE
Source: Sony’s Blog