Some iPhone 3G or iPhone 3GS users have reported that the recently available downgrade through RedSn0w causes crashes and the ‘no signal’ status when using UltraSn0w with baseband version 05.13.04, after switch back from the iPad baseband to a hackable iPhone baseband firmware. Luckily iPhone Dev-Team have worked out the solution: reinstall Mobile Substate and UltraSn0w.

Reinstalling software may seem to be in the same category of tech support voodoo as jiggling the power cable, restarting your machine, or turning your router off for exactly fifteen seconds, but sometimes there is real wisdom in this technological mysticism. You can reinstall Mobile Substrate and UltraSn0w through the Cydia package manager.

1. You should be able to find Mobile Substrate in Cydia under Manage -> Packages. Tap on the tweak to go to its Cydia page.
2. On the page for Mobile Substrate, tap modify in the top right corner.
3. Select reinstall.
4. Instead of confirming, press continue queuing. This will allow you to make a batch of more than one reinstallation, and should save you some time.
5. Go back to Manage -> Packages, Select Ultrasn0w
6. In UltraSn0w’s Cydia page, tap modify, then reinstall and confirm.

Both apps should reinstall. The issues with the baseband causing crashes and ‘no signal’ in the status bar should be resolved.

Did it fixed your problem?

via ijailbreak