My solution
Hi everyone, my name is Gustavo and I live in Brazil, so my English is not the best. After spending a few days with the same problem as described, I found a solution and Id like to share.
I have a jailbroken Iphone 4 that got frozen after an upgrade on Cydia. Same thing as the others, Apple logo for a few minutes and than a semi-frozen spinning wheel.
After some research, and innumerous attempts, I found a way to put your phone alive again. Download the latest version of Redsnow, go to extras, put your device on DFU mode and hit Just boot button, that will boot your device tethered. A few minutes later, my phone was working again
. but tethered.
After getting my phone back, I decided to find what happened, and how to solve it.
If you dont know for sure what caused, the best thing is to restore your phone using Itunes. So, the process is easy to find on Youtube, and you just have to search for restore iphone.
Still, I had to find what made my phone freeze
Well, in my case the solution was related to a stupid idea I had a few days ago. Im running iOS 5.0.1, but I had an App the required 5.1.1 for the latest upgrade
The genius here, edited the information inside the iphone using Ifunbox, and changed the iOS version number from 5.0.1 to 5.1.1. GREAT, I could bypass the limitation from my app, and downloaded the latest version.
Two days ago, I decided to upgrade my data counter app, that I had installed by Cydia. When I did it, Cydia decided to uninstall Corona Untether, once my system was running 5.1.1, and this Corona needs an iOS 5.0.1 or 5.0
So, long story made short, when I upgraded Data Counter and lost Corona Untether, I lost the capability to boot my phone.
I changed my iOS version number back to 5.0.1, installed Corona again and rebooted smoothly.
I hope that this info may help you guys.
Best regards.