Q: iphone 6s plus not getting backup to icloud on ios 9.2

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Please check that your device is correctly connected to the wifi/internet (settings > wifi) and is plugged into a power source, also check that you have enough space in iCloud for your back up.

You can check the space available at settings > iCloud > Storage and the space needed for the next back up at Settings > iCloud > Storage > Manage Storage > BackUps > This Device > Back Up Options > Next back up Size (wait for the spinning gear icon to finish).

Assuming you meet the requirements for iCloud back up, you should try a forced shutdown to begin with, hold down the side/top and home buttons together until the device shuts down, then restart it by pressing the side/top button.

Next, try connecting the device in a new location (different WiFi network)

If your back up continues to fail, you might try turning off BackUp on your mobile device (Settings > iCloud > BackUp), restarting the device and then turning BackUp back on again.

If this doesn’t help turn BackUp off again, delete your existing back up from Settings > iCloud > Storage > Manage Storage > BackUps > This Device (scroll down to the bottom) > Delete BackUp, restart the device and then turn BackUp back on again.

If you are still unable to complete a back up, try signing out of iCloud (Settings > iCloud (scroll down to the bottom) > Sign Out (you will need to enter your password at this stage), restart the device and sign back into iCloud at Settings > iCloud.

The next thing to try would be to reset your network settings. (Settings > General > Reset > Reset Network Settings)

Resetting your network settings will clear your current cellular and wifi network settings, including saved networks, wifi passwords and any VPN settings you might use. It will affect internet connectivity but won’t impact on telephone services since these settings are auto configured by your carrier. It may take a few moments to re-enter all your network settings but it shouldn’t cause you any major problems. If you are comfortable re-entering your network settings, you may wish to try this step a little earlier in the troubleshooting procedure, say after the forced shutdown suggested above.

If this doesn't help, try turning off some items for back up in a pattern to try to establish if your problem is being caused by specific data on your device. You can do this at Settings > iCloud > Storage > Manage Storage > BackUps > This Device > Back Up Options.

If you still aren’t able to complete a back up to iCloud, you may wish to try restoring your phone which you should do by making a back up to iTunes via your computer and restoring from that.

Being able to back up to the cloud can be very useful, especially if you don't have access to a computer or have infrequent access to one, however unless you specifically need to use iCloud for back up, you will find backing up to iTunes significantly more convenient and possibly more reliable. However if you back up to iTunes be sure to encrypt the back up if you want to keep your health data and passwords etc.

More about iCloud v iTunes Back Up

Backup problems after ios 9

Backups – Troubleshooting IOS

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I have tried all of the above and I can get the backup to work TEMPORARILY only.  For instance, the device will back up automatically one or two times after either deleting the existing backup, signing out and back in, or doing a hard reset. I can manually "back up now" and it will sometimes work but it will stop working after a couple of backups and will not work again unless all or some of the above steps are followed. This ios 9 update has ruined the security of the daily backup for me. It's a lot of time and work and sometimes I forget. I am hoping 9.3 will fix this but all I've read online about 9,3 the back up problems are not even mentioned, so I don't have hope. This worked flawlessly with 8 but since 9 it has been nothing but a constant headache for 4 MONTHS and no hope of any help from Apple.

I am having the same issue.  It started this past Saturday.  I don't know if Apple is going to fix it with 9.3 or not.  I am wondering if I should just go to an Apple store to see if I can get it fixed, or my device swapped.  Again, used to work fine but no more.

Had a chat with Apple support and was told that Apple is aware of it and it will be fixed in a future update.  However, just updated to 9.2.1 this afternoon and the issue persists.

HI, I've got the same issue that iCloud doesn't backup even when running it manually. I've tried all the things possible even setting up my iPhone as a new one it still refuses to backup. "The last backup could not be completed." Will try update iOS as above but doesn't seem like it'll work from others comments. For now have to backup on itunes.

I am in the same boat.  I have tried every trick I have found online all to no avail.  Not sure if swapping out the device will fix it?

trooper this started on my end thursday which was my last successful back up. Swapping out the device will not solve anything it is not hardware related. I tested this out bu installing my icloud accoubt on a brand new ipad and still did the same error

This issue solemnly lies exclusive with each apple id. That is why the number of affected users affected with this they have not solved because it is not happening widely. I just tested and created another apple id and was able to back up perfectly fine on both devices that are crippled right now.

Same here. Treid everything. Contacted Apple - Full Restore. Can't enable iCloud Backup. There are similar threads here with over 10.000 clicks.

This issue solemnly lies exclusive with each apple id. That is why the number of affected users affected with this they have not solved because it is not happening widely. I just tested and created another apple id and was able to back up perfectly fine on both devices that are crippled right now.  Nothing hardware related.

Went to Apple Store yesterday and no dice.  They would not swap out to test.

So its Apple ID related I get all that.  But how can they not have a fix for this?

Exactly all symptoms you have described sound exactly like mines.  I do want to mention now that all of a sudden miraculously it started working yesterday.  I am able to pass the icloud back up now and can run it now.  The problem is i have not been able to get a successful back up, it fails almost halfway mark.  My back up is roughly about 22 gigs, i am now trying to do a backup now excluding my photos which take up the most space.  i will give you a status, how are you doing.  Have you tried it today?

The ios 9.3 beta does not fix this issue at all. I am having this issue also and im very frustrated.  I dont even get an option to delete my old iphone 6s backup.  Apple needs to fix this issue badly, as it has ruined my experience with icloud