My DVD player was earlier upgraded by firmware 3.1 for DV-410 V and now i upgrade with firmware for DV-420 V 2.4 and I changed the numbers as it is firmware for 410 to fit. DVD player upgraded that firmware and it works, but now I want to put it back to the firmware 3.1 for DV-410 V and when I put the disc with the firmware the DVD shows CD cannot be read. What should I do? Thanks.
I changed DV-420 Firmware V 2.4 - YKF9930A to YJB8A31A (Firmware number 3.1. for DVD 410 V) Thats the firmware i have on my dvd now. I tryed to upgrade it with YJB8A31A firmware 3.1 but dvd answered CD can not play.After i saw your response i checked in the dvd options for the name of the current rom version, but it was a different name than i thought. It was YKF9930A and after that i changed the name of firmware YJB8A31A to the name of the current rom version and after that CD was accepted and i managed to upgrade my dvd. Now my dvd's rom version is YJB88A13A and everything is working fine like it did before this adventure..on the 420 firmware subtitles were bigger but it missed the darker background of the sutitles when the picture on the tv is white if there were more black in the background of the subtitles it would be ideal . Thank you for helping.