Tried updating my jailbroken iphone
Normally, restoring the factory settings is done by syncing your i Phone with i Tunes and then clicking restore.
To execute this, hold down the home and sleep/power buttons simultaneously for 10 seconds and if you are lucky this might do the trick.Check @Pangu Team, @taig_jailbreak, @saurik, and /r/jailbreak for news and updates.You can use Cydia Impactor if you need to un-jailbreak an 8.1-8.4 device without restoring. To search this page for a keyword (such as "baseband" or "SHSH"), use Ctrl-F on Windows, Command-F on Mac, or this feature in Safari on i OS.You may also continue holding these buttons for 20-30s but if your i Phone doesn’t show any response in first fifteen seconds then there is a probability that it won’t show it even in hours.Although this option erases all the data and settings on your smartphone, it is a better option than just seeing your i Phone dead.For Windows 7 and Vista users, be sure to run redsn0w as Administrator in “Windows XP Compatability Mode” if you encounter any errors, you do this by right-clicking on the redsn0w application and selecting XP Compatability.
Update: redsn0w 0.9.6b6 has been released and all those who wish to unlock i Phone 3GS or i Phone 3G should use that version instead since it will provide for better battery life.
Redsn0w 0.9.6b5 jailbreaks i OS 4.2.1 but also provides the added ability to install baseband firmware that can be unlocked for the i Phone 3GS and i Phone 3G.
For other i OS devices, redsn0w 0.9.6b5 will simply jailbreak the device but some models will be a tethered jailbreak.
Many complain that their i Phone won’t turn on without knowing the proper reason behind this condition.
If you’re one of them, then don’t worry as there are lots of things you can do to your beloved smartphone before concluding it’s dead and needs to be replaced.
That often works to move beyond the stuck Apple logo.