Uninstall 6.20 TN-D Permanent to 6.20 PROB-4

1.Download this file: http://www.mediafire.com/?6rf28xxd93lzm4l
  Extract and copy the 620TND_PPATCH folder then paste to PSP/GAME folder

2. Remove Psp in USB cable then go to GAME the run the 6.20 TN-D Patch

3. Next your device will reboot in a seconds then in the seconds then in the screen you will see

UNINSTALL 6.20TN-D PATCH PRESS X-to uninstall / Press O-To Exit...

4.Press X To uninstall 6.20TN-D PATCH......

5.after Uninstall 6.20TN-D you psp will be reboot for a secs.

go to ur psp then PRESS SELECT BUTTON to in your psp....Then Find "Shutdown Device"

6.Your Device will Fully Off...then Power ON your psp then go to your...PSP
Then To System Then Check The version of your psp...




NEXT INSTALL 6.20PRO-B4

1. Download this file: 620PRO_B4

 After you download, extract then copy folders in your PSP/GAME folder.

2. First GO To Your psp then go to games then run PROB-B4 Then your psp will be reboot..

2. Second Run 6.20 Pro-b4 Recovery......then the device will be reboot for a secs.

3. Third Run 620 PRO-B Permanent
Run 6.20 pro-b
PRESS-X To agree

next Press X-to Agree Test

4. Run Again 620 PRO-B Permanent

run 6.20 pro-b
PRESS-X To agree

Next Press-O- to Disagree to test...

5. Congrats you are in 6.20 Pro-b4 firmware :)