I recently bought an iPhone 6s and I'm trying to restore my backup from my old iPhone. But my iPhone 6s is not compatible with the version of iTunes I currently have, so my laptop prompted me to update it to version 12.6.1. Halfway through the installation, it stops, and a window pops up that says "iTunes has an invalid signature. It will not be installed."
I can't restore the backup until I update iTunes, so I tried to back up my old iPhone to iCloud, but every time I try, a window pops up that either says "there's not enough space to complete the backup" or "the iPhone has been disconnected" (which it hasn t.)
I don't have time to go to Verizon or the Apple Store for the next 3 or 4 days, so I'm out of options. Any suggestions?
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