At first i would like to upgrade my software from 1.13 to 1.20.When i upload the new firmware 1.20 Unlocked GSM, i got a serious problem that the rom is error and can't complete the upgarde. I try so many time and the thing keep going on. Then i forgive the upgrade but now the software didn't change but my firmware up to 1.71 from 1.5x (i forget). What should i do ??