It has completed now. I notice it chomped up a lot of space on my C: drive while it was backing up so maybe the slowness is due to that. Funny thing, my iPhone summary showed disk space down from 78Gb to 68Gb and then after I synced, reverted to 78Gb. I am guessing it needs a 10Gb buffer to do the backup?
If you have an SSD system drive you might want to take a look at Relocate iOS device backups. Estimated free space before, during and after syncing can sometime be a little erratic, though a leap up and down of 10Gb seems excessive.
So I guess I am good to go until there is a next update in which case I had better steer clear of that. Am I correct in guessing that I can run 10.0.1 and continue to sync with my current Vista 32 bit PC running iTunes 12.1.3?
As far as I can tell, yes.
If something goes awry with my iPhone, will I be able to restore from this backup without issues?
Again, to the best of my knowledge yes. It might pay to make an iCloud backup as well to give yourself alternatives. I've just expanded that tip above into a proper user tip here: Archive iPhone backup in Windows.
OK so I don't understand this. 12.1.3 is obviously compatible with an iPhone running iOS 10. It just doesn't do the update.
Apple probably want to encourage everyone to move forward. Sometimes there might be legitimate technical changes that break backwards compatibility, sometimes they might just decide it is time. Cutting off Vista and XP at the same time looks like that kind of decision.
Is there a lot of work involved for Apple to make the update work on it? I am guessing there isn't. So why don't they just go ahead and make it work?
It is more effort to code for multiple versions of Windows. You're force to coded to the least capable platform and write your own support files for all of the tasks that it won't perform natively. Back in the day QuickTime did in software what PCs now do in hardware. Apple have dropped QuickTime on Windows and removing support for XP and Vista presumably lets them drop other legacy code.
Also, nothing to do with this issue but does Touch ID no longer work with iOS 10? Before, I could just place my thumb over the home button and it would unlock. Now I need to press the home button.
Yes, that does seem to have changed. I normally press the home button so it doesn't really bother me that much.
Thanks again
You're welcome. 🙂
tt2