I just received a 3gs v4.1 and it is unlocked but when I insert sim card all the phone shows is searching, I use the same sim in a 3g without a problem, I am with T-Mobile...please advise...John,usn,ret

What is the modem firmware?

hi, appreciate any help you can give me,....the Modem Firmware is 05.14.02.....thanks....John,usn,ret

For T-Mobile, make sure you disable 3G in the iPhone network settings or it will constantly search. T-Mobile's 3G doesn't match AT&T's so the device will continually search and fail to connect to T-Mo via 3G. Will need to be disabled for the phone to function.

Hi, Thank you for the reply, the phone 3g access has been off and it still just searches, I use this sim card in my 3G and it works perfectly....maybe it has something to do with the modem in the 3gs, the modem is 05.14.02 the modem in my 3g is 05.11.07...is there anyway to change the modem settings....appreciate your valuable time...John,usn,ret

Originally Posted by NAVYSSN575

maybe it has something to do with the modem in the 3gs, the modem is 05.14.02

Yes that baseband version does NOT work with ultrasn0w - if you have been told that it was "unlocked" then this could either mean that you could "unlock with ultrasn0w" or that it was "commitment free" - which means that you paid lots of money to get an "officially unlocked iPhone"

If you need to get ultrasn0w working, there is a solution - but it is not recommended for everyone, there are some significant issues on the 3GS you need to take into account before you decide if you want to do this. There is no way to reverse the baseband update.

Dev-Team Blog - Ultra-recycle

Thanks you so much for your time, I will check this out...I tried redsnow today but ended up with a firmware version 4.2, the phone is not searching anymore, have the apps etc, but still the sim won't work, will try to go back to 4.1...thank you so much for your time...John(SSN575)