My 3gs (4.1/6.15) had lots of problems but with the help of some fine people on this forum I finally got it loaded with 4.1 and JB. I went fo the unlock with Ultrasn0w and it seems to have worked, but I am stuck on "No Service". I have tried resetting, rebooting and reloading Ultrasn0w but sitll have the No Service. I have this phone only for overseas travel, so if I can not put just about any sim in the phone, it does not have much value to me.
if you already have 6.15 on your iphone do not need to update to 6.15 baseband again. Your problem can be fixed by running redsn0w without any option selected, this way will hactivate your iphone. Should work ok after that, if not install ultran0w again
with redsonw 0.9.9b7 select jailbreak, when you get at the menu where you ca sellect cydia deactivate etc, do not select anything and press next, wait until the iphone is jailbroken and should have signal now, if not install ultrasn0w again
I did as you suggested, but just to clarify when I get to the options screen I DID select install Cydia but left the rest blank. It reJB but still have the No Service message. Reran Ultrasn0w, but no changes. Still sitting here with No Service....
now what baseband you have 6.15?You can try a new custom restore or can try as iYeow said to update the baseband again,let me know if any of those fixed it
I think I may have made something worse. I tried redsn0w again with no changes. I then went with redsnow and reloaded (reinstalled) the ipad baseband. Now I still have the "no signal" message, plus my wifi is no longer working! iPhone shows the wifi connection at the top of the page, but not working. I tried resetting, forget this network and restore all settings but to no avail.
The phone is too small to use as a boat anchor! So now what?
Restore to stock 4.1 , kick it out with TU or restore to custom firmware 4.1. If you have the official sim, let it trigger from Emergency screen to Homescreen, otherwise hactivate but may cause problems. Test for signal after installing Ultrasn0w.
Use Redsn0w 0.9.6b6 or Limera1n to jailbreak if you restore to stock 4.1