iphone 4 update to ios 7 failed - cycles in and out of restart screen

IOS7 appears to have been installed on my Iphone 4. It comes on, apps start but then the "restart screen" appears after 1-30 secs. After another 20-60 secs, the "restart screen" disappears and the app begins where it had left off.

Just to be clear, by "restart screen" I mean a black background with centered white apple and a progress bar beneath the apple. The progress bar lights up to maybe 1-3% but never any further (and sometimes less) no matter how long it remains in this state.

Solution 1:

If you have a recent backup (and thus aren't afraid of doing a fresh install and restore), there are a few things to try - all of them involve putting the phone in a mode that makes iTunes prompt you to do a complete restore/update/sync afresh.

• Put the phone in Recovery Mode, and restore it.

If that doesn't help:

• Try putting the phone in DFU mode and restoring it.
• If you find the above instructions difficult to follow, especially with the timing between actions
  • just download redsn0w (look for the download links at the bottom of the blog post)
  • run redsn0w
  • go to the DFU option
  • it will guide you step-by-step to put the phone in DFU mode
  • once that's done, restore it from iTunes. Although redsn0w is primarily meant for jailbreaking, it is very useful for putting a phone in DFU mode.