Dreaded "session could not be started" syncing problem.

When I get this error, I just put device in Airplane Mode, run the backup, then re-enable the wireless communication. Quick and easy way to deal with the PIA.

Three F'ING hours!!! That's how long I've been trying to get my calendar from my iphone to my imac...and THIS is what works?! First of all, thank you iBuckhead. So appreciate the fix but common...really?! Apple can't figure this out with all of their "cut and paste this garbage line of code into terminal" but some random who-on-the-planet-actually-was-able-to-figure-out-this-work-around thing like enabling Airplane mode worked?! Good Lord....what's next, Contacts won't sync so I should call my mom and ask her how her day was and then connect my phone and magically it'll work?!

Happy to have my calendar back on my desktop byt sweet cherry pie am I the only one who thinks this is RIDICULOUS?!?

After getting a new PC and reinstaling iTunes, I'd been receiving this alert when trying to backup/sync my iPhone4, but none with iPad using the same cable and environment. What solved my problem was setting the iPhone to airplane mode. I guess it was something related to sync over wi-fi (that was disabled on both devices, but was somehow causing these issues).

I've been searching for days and I found a solution. You need to put your phone in DFU mode. Here's a video

www.youtube.com/watch?v=F4PQ-HWfs10

I've been struggling with this for the past hour and I've found that disabling the wifi adapter in my laptop allows me to backup my phone. As soon as I re-enable the wifi adapter I get the dreaded error message. Turning off the wifi adapter again allows me to immediately backup.

worked like a champ! 3 years after the original post we/ latest version of iOS 7

Had this problem on a replacement iphone4 that I was trying to restore a backup onto (right after upgrading the phone from iOS5->7). Not sure if all steps were needed since it seemed to be a problem with the computer forgetting that the phone was trusted:

• Restarted phone

• Restarted mac

• Turned of wifi syncing on phone

• Mac prompted me to let the phone trust the computer

• Phone prompted me to trust the computer

• Click restore from backup in iTunes – it worked.

Here's what worked for me.

I've got 4 iPhones on the same iTunes account. My iP6+, Mrs W's iP5, a 3GS used instead of a landline and a spare iP4. The iP6+ and iP5 are backed up regularly but the 3GS and iP4 had not been backed up since April (3 months ago). Tried to back them up yesterday and although the 3GS was fine, I got the error message for the iP4. I checked the backup location on my PC and deleted any old backups, just leaving the four. I tried a hard reset of the iP4 and tried resetting Network Settings. I took the SIM out, cleaned and replaced it. No problems with iTunes recognising the iP4 (or the other iPhones) but still gave the error message when I attempted to sync or do a manual backup. I desperately did not want to muck about with the backup files and risk corrupting those for the other three...

... in the end I erased the iP4 completely and restored it from it's back-up, then synced it. Eureka! The backup file now shows that it's been updated. Logic suggests that somehow the iOS on the iP4 had become corrupted. Had the restore-from-backup not worked I would have set it up as a new phone. Fortunately not necessary.

I realise this won't solve the problem for everyone as I suspect there are several reasons for the error message, but it's probably worth trying.

Worked great two years later! I have an iPhone 6, here is what I did:

1. set phone to airplane mode

2. restart phone (still in airplane mode)

3. turned wifi off on my laptop

4. connected the phone to my laptop in itunes

5. back up started!

thanks!

thank u very much