Since the iOS7 upgrade on phone (iphone 4) my computer cannot seem to maintain it's authorization. After a reboot it loses it, then I can't get it to authorize again. Each time I authorize it says I "have now authorized 1 out of 5 blah". But if I try to sync it 1 minute later it says the computer isn't authorized and to authorize it. Finding nothing on google, very old posts with solutions that I have tried and gotten nowhere with as yet. Any ideas / suggestions?