Update iPhone through iTunes without backup?

Hi I have kinda the same problem. But, i do not see why, maybe it has the same solution.

I have an iPhone 6S, 128Gb, according to iTunes, it has 57.36Gb free, (so 46.28 used?). I have a Macbook Pro, Sierra 10.12.1, 256GB SSD, with (according to About my Mac/Storage) 91Gb available. I am trying to update from iOS 10.1.1 to 10.2. My backups are set to automatically backup to iCloud, the latest backup being 1:16am this morning. When i connect my phone and click Update, it extracts the software, then starts to Backup my phone, subsequently producing an error telling me there is not enough space on my computer and to delete things. Clicking ok then stops the update process. I also tried clicking the 'x' when it was backing up, also stops the Update process. So, my questions...

1) Why is it forcing me to backup my phone to my computer, when i already backup automatically to iCloud (have 200gb storage on iCloud) AND it was backed up 9 hours ago.

2) Why am i being told i have no room, when my phone has 46gb of used space and my MacBook apparently has 91Gb available.

3) Why can't I / How can i skip the backup and still update my phone.

Cheers in advance.

I had this exact problem and I finally found a solution that worked for me. Just to confirm for others, If iTunes does not let you update your phone without backing it up first and it gives you the error that you do not have enough storage on your computer (whether you select iTunes or iCloud options in iTunes), try the following:

Turn on Activation-only Mode in iTunes - Apple Support

Try below found it from http://klauskjeldsen.dk/iphone-3g-disable-slow-itunes-backup-mac-and-windows/:

mac users:

1. Quit iTunes.
2. Open a Terminal (Applications > Utilities > Terminal)
3. Type or copy the following command:defaults write com.apple.iTunes AutomaticDeviceBackupsDisabled -bool true
4. Open iTunes.
5. Connect the iPhone.
6. Make Sync without backing up.

To enable automatic backup in iTunes again use this command instead:defaults write com.apple.iTunes AutomaticDeviceBackupsDisabled -bool false
Note: If you previously have used the command line option that entirely disables the backup feature, then type this command as well to enable to backup process:defaults write com.apple.iTunes DeviceBackupsDisabled -bool falseRecommendation: If you choose to disable the automatic backup process, it would be a good idea to manually making a backup it once a while to get a safe copy of text messages, call log and like (just right-click your iPhone icon in iTunes).

windows users: (updated)

Windows users can use the same approach:

1. Quit iTunes.
2. Press Win+R (opens the Windows Run dialog)
3. Type or copy the following command:“%CommonProgramFiles%\Apple\Mobile Device Support\bin\defaults.exe” write com.apple.iTunes AutomaticDeviceBackupsDisabled -bool true
4. Open iTunes.
5. Connect the iPhone.
6. Make Sync without backing up.

If you do not want to back up your phone first, you are living VERY dangerously. However, its your phone, so try this:

Get help with over-the-air iOS updates - Apple Support

Have you tried:

Remove and download the iOS update again

If you still can't install the latest version of iOS, try downloading the update again:

1. Go to Settings > General > Storage & iCloud Usage. Under Storage tap Manage Storage.
2. Find the iOS update in the list of apps.
3. Tap the iOS update, then tap Delete Update.
4. Go to Settings > General > Software Update and download the latest iOS update.

https://www.apple.com/retail/geniusbar/

I am having the same problem.

Back up on icloud (no difficulty).

30GB available on my phone.

But won't allow update without backing up on my Mac first.

I turned off Activation-only Mode in iTunes but now every time I open iTunes it disconnects my phone. How can I get iTunes to still see my phone but not run the back up?

Having the same issue...

Michael Black wrote:

...

Similarly on your iPhone, if the update downloads but cannot run, you are likely too short of free space on the phone itself.

But, as I recall, the update should tell you that.

Onnaderuion wrote:

I have 4 gigabytes left, and when I notified an Apple Support employee, they said the storage space wasn't a problem.

It may not be the only problem but it is an issue. You will see a noticeable improvement if you get more free space (larger hard drive/delete some stuff off current drive).

Backup to iCloud

Onnaderuion wrote:

Hi,

I keep getting an error when trying to update my iPhone 6 to 9.3.4 over-air, and after research tried to update it using iTunes on my Mac. However, every time I try to update, iTunes forces me to back up my phone first. I do not have enough space on my Mac to backup my phone, so an error pops up and the update stops. I do not want to back up my phone, but I do want to update my phone.

So with not enough room on your Mac to even back up your iPhone, when your Mac crashes (and it will), you will lose everything on your Mac in addition to all data on the iPhone.

You should keep a minimum of 10% free space on your computer.

Also, you should regularly back up your iPhone.

My guess is if you do not have enough free storage space on your Mac to backup, you almost certainly do not have enough space to download the update, uncompressed it and run it. Your problem is your Mac has far too little free disk space.

Similarly on your iPhone, if the update downloads but cannot run, you are likely too short of free space on the phone itself.

I believe it should, but as the free space gets critically low, iOS (or OS X too) can get flaky and behave in unexpected ways.

PERFECT! Thanks!!!