As the phone begin to reboot, press and continue to hold the + volume button. This process starts the iPhone in "Safe Mode." It may allow you to return to the Lock screen. Perhaps this will assist you in restoring the device in iTunes. I would love to hear how this turned out for you.
Thank you,
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Michael
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Michael
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=== Update (01/04/2016) ===
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Try the following:
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1. Disable iCloud syncing
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When stuck in iPhone blue screen of death in iwork, one workaround to alleviate the iWork-related reboots is to disable iCloud syncing for Apple's Pages, Keynote, and Number apps.
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2. Use the freeware ReiBoot
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There is an excellent program called ReiBoot. It is the freeware and you can use it to restart your iPhone in blue screen of death. It will never cause any data loss or damage to your iPhone.
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Download and install ReiBoot on your Windows PC (Windows 10/8.1/8/7/XP/Vista). Mac users go to ReiBoot for Mac and it works on Mac OS X 10.11 El Capitan, 10.10 Yosemite, 10.9/10.8/10.7/10.6.
You can try the following step:
As the phone begin to reboot, press and continue to hold the + volume button. This process starts the iPhone in "Safe Mode." It may allow you to return to the Lock screen. Perhaps this will assist you in restoring the device in iTunes. I would love to hear how this turned out for you.
Thank you,
Michael