1.Use USB FLASH KEY from 64mb upto 2GB. I recommend upto 2GB but you could also use bigger ones but they using different adressing model
this could be issue for some models.

2.Format the USB FLASH key to FAT16 or FAT32 filesystem don’t be lazzy and DON’T use NFTS for this case 1)
use USB FORMATER 2)or any others formatting tools.

3.Go to WDTV menu System→About there is version notice it you will need this number later.

4.Unpack firmware package to USB FLASH KEY to root directory there have to be 2 files WDTV.BIN and WDTV.VER.

5.Open with notepad or any textplain3) editor and change version in WDTV.VER to higher then you have in WDTV now if you dont change this new firmware will not detected as new one.Save the file.

6.De-attach all USB devices from WDTV unplug power supply wait 5-10sec plug-in USB prepared USB FLASH KEY and plug-in power supply.

7.Wait and dont reboot WDTV durring flashing process