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pgoodwin Author

Level 2

164 points

iPhone Sync Still Fails to Start in iTunes

iPhone SE running iOS 12.0.1

iMac running Mac OS 10.13.6 and iTunes 12.6.2.20

When I connect the phone by cable, it shows up in iTunes. When I hit "Sync", it tries to start syncing but the sync never starts - I get the message: "The iPhone could not be synced because the session failed to start"

I'm syncing / backing up to the Mac - not to iCloud. Also, I rebooted the Mac and the iPhone - no help. The iPhone won’t sync to the computer in iTunes whether I use the Lightning cable or trying to sync over WiFi.

The iPhone synced fine prior to the iOS 12 update. This is my first attempt at syncing running iOS 12. I have an iPad Air 2 running iOS 12 and it syncs fine on the same Mac / same iTunes.

I fixed this problem by re-starting the iMac in Safe Mode, then re-starting the iMac in normal mode, but a few days later, when I again tried to sync the iPhone, and the sync failed to start again.

iMac, macOS High Sierra (10.13.6), 12 GB RAM mid 2010 21.5”

Posted on Oct 17, 2018 9:09 PM

Top-ranking reply

SiHancox

Level 5

4,953 points

Posted on Nov 3, 2018 6:55 AM

pgoodwin wrote:

I don’t see this in my library:

Finder (~/Library/Application Support/MobileSync/Backup/)

Not sure why you can't find the BackUp folder, I don't believe you can alter it's location without Terminal hacking, so just make sure you are looking in the correct Library, it's the "User" one (ie. under your name).

A comment you made earlier is interesting, when trying to Update to 12.1 a successful BackUp was made, but you could not then do this again manually. Syncing and BackUp are two different processes, you even have two buttons in iTunes for them, "Sync" is bottom right while "Back Up Now" is towards the middle, when you tried the "manual backup" did you still click the "Sync" button or did you try the "Back Up Now" one. You might find the latter works, and if that's so I would guess the issue is purely on the syncing side of things, may be in the form of a conflict in a setting.

You could try selecting your device (top left) and in the sidebar under "Settings" select each category (Music, Films etc) and untick the "Sync" box top left.

When you have unticked everything from Music to Photos under the Settings sidebar, try the Sync process again.

If you still have the same issue after that, then I don't believe you have much option other than try a Restore as New, in other words wipe your iPhone. If you have iCloud syncing enabled on your Mac (or any other device) then when you log back in on your clean iPhone and enable iCloud syncing your data will come back down from the cloud.

As you can see this can include Contacts, Calendars etc., so you get a good start in getting the device back to how you had it, although you will need to add back your Mail account and obviously download your Apps again.

Hope some of the above helps.

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38 replies

SiHancox

Level 5

4,953 points

Nov 5, 2018 6:41 PM in response to pgoodwin

I've seen a few similar issues on this forum over the past year, but must say it's not been that many, regarding the form, I think that's just standard practice because they need to know what the software is at both ends of the issue so they can hopefully track it down and come up with a fix.

When you said "Updated to 12.1", how was that done, if it wasn't via iTunes then it doesn't "replace" the OS, OTA (ie. update via the devices) just amends the existing OS so an issue may still survive the process, only via iTunes does it completely delete/replace what's on your device.

pgoodwin Author

Level 2

164 points

Nov 5, 2018 6:40 PM in response to SiHancox

I upgraded to iOS 12.0.1 a few months ago by just using the phone via Wi-Fi. I did it the same way when upgrading to 12.1. So if using iTunes is the only way to completely replace the OS, then perhaps the best thing is to completely earse the phone and start from scratch using iTunes. Then I’ll do a restore from the backup.

pgoodwin Author

Level 2

164 points

Nov 5, 2018 8:17 PM in response to pgoodwin

Bummer. I didn’t think about it before erasing the phone, but all the music and playlists were erased, and since I can’t sync, I can’t get them back onto the phone via iTunes.

i can go to the Music app on the phone and download songs manually one at a time and create song lists there, but you can only download music to the phone that you purchased from the iTunes Store. 12,000 of the 14,000 songs in my library are from ripped CDs, which don’t show up on the phone unless you can sync in iTunes. I’m screwed.

pgoodwin Author

Level 2

164 points

Nov 6, 2018 5:09 AM in response to SiHancox

I’ll try erasing and setup as new and see what happens.

i don’t have a backup in iCloud to use. I did see a Message on the iPhone screen when I was about to restore that I could hold the phone near another device (iPad) and restore wirelessly - I can try that too

thanks

pgoodwin Author

Level 2

164 points

Nov 6, 2018 7:04 PM in response to SiHancox

I did another erase and set it up as a new phone, and it Syncs!!!!!

Because I have one Apple ID for the store and one for iCloud, it turned out (after a couple of tries), the setup as a new phone went OK using the iPad wirelessly to get my data in correctly. It took me a long time to add back in all the apps one at a time - I had taken screenshots of my 4 screens of apps and folders on the phone before I erased it, so I manually downloaded them from the App store.

Thanks for all the help

SiHancox

Level 5

4,953 points

Nov 6, 2018 9:39 PM in response to pgoodwin

Glad you have sorted, the "fresh" iOS together with not using an old iPhone "BackUp" appears to have been the answer then, I would guess that whatever "Setting" or "Corruption" was behind the issue, by using the above was not transferred back in the Restore process, just make sure you delete all your old iPhone BackUps so they can't get used by mistake in the future!

All the best.

Dec 9, 2018 4:25 PM in response to pgoodwin

iPhone Sync Still Fails to Start in iTunes. it's happening to me and alot of iphone users now, and apple won't fix. Hate this, expescecially making to impossible to simply load music on my phone without having to go thru itunes, controlling everything. Just like they "throttle speeds on older devices' (something they denied for years, but then finally admitted to it when the facts were confirmed, just to force us buy new and upgrade out of frustration. it's disgusting and shows no consideration for their users, just their profits. . also, Now, after the last up-date, why do I need to keep signing in with my apple ID everytime i go to use App's???! even stuff that's not apply related.....