[IPhoneMD]

You may want ("want" is a bad term,"need" is better) to do a full format via the iPhones settings(erase all) this could take up to two hours. When finished do a restore in iTunes, (Do not reinstall any of your personal data or programs just yet). After the restore go back and rered(only checking cydia) and reultra. This way you are eliminating any SW conficts that may be from old unlock code. After you unlock with ultra reboot put your sim in and test your carrier.Now you can start to replace your personal data. Basically you are jailbreaking and unlocking a new iPhone.
Please repost or send me an email afterwards and confirm whether or not this did it.Trying to eliminate any SW conflicts.
IPhoneGuru@tx.rr.com
J

[TheJoshX]

Originally Posted by IPhoneMD

You may want ("want" is a bad term,"need" is better) to do a full format via the iPhones settings(erase all) this could take up to two hours. When finished do a restore in iTunes, (Do not reinstall any of your personal data or programs just yet). After the restore go back and rered(only checking cydia) and reultra. This way you are eliminating any SW conficts that may be from old unlock code. After you unlock with ultra reboot put your sim in and test your carrier.Now you can start to replace your personal data. Basically you are jailbreaking and unlocking a new iPhone.
Please repost or send me an email afterwards and confirm whether or not this did it.Trying to eliminate any SW conflicts.
IPhoneGuru@tx.rr.com
J

I think I tried this in 2.2 and it might of worked, and I'll try again now. Thank you very much for helping me so far, and I really, really appreciate it that you've taken time out you've day to help me, a frustrated iPhone user.

No, it didn't work. When I did a full format, when it finished (when I checked), it kept rebooting onto the apple logo and freezing with the little (_) thing spinning.

So I put the iPhone into DFU, and restored using iPhone and did all the steps again. No dice.

[wraith1138]

For T-Mobile users with "No Sim" and/or "No Service" issues after Ultrasn0w:

Solution: get a new SIM from T-Mobile. The SIM I was using came with a phone I purchased in 2002 which apparently old enough to cause issues with newer phones. The swap was free as the card was undamaged and my 16gb 3G recognized it immediately.

I spent the better part of two days trying to figure out what the hell was causing the issue and tried everything people in this thread suggested when a friend who had seen my SIM a while back suggested that it might be too old.

I haven't seen this fix posted anywhere yet so hopefully this helps some equally-frustrated people out and if so, feel free to hit the Thanks! button

[pderby]

The thread at Click Here is where I posted my experience with having to replace my old T-Mobile SIM.

[dakomo]

Cydia has NEW update for the UltraSnow. After installing and rebooted my 3G iPhone retrieves carrier signal in secs! Faster than I had UltraSnow installed the first time.

I highly recommend everyone to update their UltraSnow in Cydia.

[The_Snowman]

Mate,

You never did let us know how this ended up, please report back ASAP

I had a lot of problems with my 3G, 3.0 iPhone, ex-Telstra which I was jail breaking to use here in Saudi Arabia.

Long story, make it short, must have been an internet glitch as one day, Cydia just decided to connect and now all is OK.

Thanks, John

[b3nny]

i'll be the third person to confirm, if you are using yellowsn0w to get a 3.0 iphone 3g on t-mobile US and you get "no signal" its probably because you have an old sim card. go to the t-mobile store, and kindly ask for a new sim card, they'll probably give it to you for free and then bada bang bada boom 3g is good to go. my sim card was 6 years old at least but worked flawlessly in my 2g. iPhone 3g is different though, as it needs a newer sim. hope that helps someone.

[xjuliephanx]

After I upgraded to ultrasn0w v91 I got the no service error but before then I was fine. I have tried restoring to 3.0 & 3.1, jailbreaking using PwnageTool and redsn0w and installing ultrasn0w v91 through Cydia and v6 offline and my signal is still intermittent. My SIM card is only about a year old so I'm pretty sure it's not that. I have no idea what to do now!

[Pinocchio001]

Hi, I found a very usefull suggestion on everythingicafé.com!
It works too, which is nice.
You have to download Bosspreffs via Cydia, untick all things, then reboot (very important!!!) form Bosspreffs.
Thenk after reboorting, go to settings, switch airplane mode on and off again, and let your Iphone seach for a network. It takes about a minute or two, so don't be impatient.
Finally, your network shows up, as if it was never lost!
Very happy indeed, and Thanks to Uncle Luke out in the icafé!