Recently I upgraded my iPhone 3Gs to iOS 4.0 and came accross a problem. I chose to upgrade my software rather than do a full restore, but when trying to sync my iPhone with iTunes 9.2 (required for the new iOS) I get the following error message.
iTunes could not back up the iphone … because a session could not be started with the iPhone.
It seems as though iTunes will not backup my iPhone nor can it restore from a backup. I can install or remove apps, and move media on and off the iPhone with iTunes and there seems to be no problems other than the backups.
I searched through the apple discussion boards and Google, and found lots of suggestions but no working solution.
I also tried an inplace upgrade of the software over top of the current installation but that did not change the situation.
I finally had to do a factory restore. Because I had backed up my iPhone before this whole process, once I performed the restore, I was then able to restore my iPhone from its backup. Then I went through the process of setting up all of the new iPhone 4 settings and preferences which were not in the backup. This also meant reinstalling all of the applications as well.
Everything is working fine now and what did I learn from this, backups are valueable so take the time to do them.

I have the exact same issue.. I am hoping it is a common glitch that apple will soon fix
Same here. My iPhone 3gs wouldn’t backup on my vista machine after doing the 4.0 and 9.2 upgrades. Worked fine on my XP and Windows 7 machines. Fixed it by resetting to factory defaults and then restoring to the Windows 7 backup. Now it backs up fine on the Vista machine
Same here. Backup works on Windows 7 after iOS 4.0 (and 4.0.1) upgrade, but not on my iMac. So I guess I have to do a full backup on my Windows 7 PC and do a reset.
I had the same problem on my new 27″ iMac but it worked fine on my Macbook. The iMac is a clone of the Macbook and it used to work fine
I think mine quit working after I upgraded to iOS 4.0. A sync on my MacBook Pro worked fine but a sync on my Mac Mini would not complete the iPhone backup step. I had to use the Restore button in iTunes > Devices > (my iPhone device) as Mark said. My apps were automatically reloaded but many other features had to be set up manually (folders on iPhone, email account, etc.). Sync with back up is successful now. But what a pain. Thanks for getting me on the right track.
Same problem here. Would love a solution from Apple someday soon.
I have the same problem on my new mbp
same problem with my iPhone. I use iOS 4.1 and iTune 10.0.0.68
And I’m guessing you guys all used Sn0wbreeze 2.0.2?
Upgraded from 4.0.1 to 4.1. Everything works except Youtube and the backups.
Youtube can’t connect.
Actually I never did jailbreak any of my phones.
Same issues on my phone. I’ve installed all the latest
software but it’s no use… same message appears every time I
connect my phone to my mac.
same here
Exact same problem.
iphone 3g, 4.2.
iMac 27″ i7
reinstalled iTunes 10.0.2
rebooted the iMac and iPhone
deleted the backup folders and tried to make a new one, nothing worked
Same issues here
Thanks for this excellent article. One other thing is that many digital cameras are available equipped with a zoom lens that allows more or less of any scene to get included through ‘zooming’ in and out. Most of these changes in the aim length are generally reflected within the viewfinder and on huge display screen right on the back of this camera.
I upgraded my 3GS to 4.3 using snow breez and when I try to restore Bly backup it says session could not be started with u r iPhone … Can u plzz help me guys
I seriously need my back up ….
Pls mail me to msr476@gmail.com
msr_476@yahoo.com
Or post here
I have the same problem about 7 months. My iPhone is slower, youtube doesn’t work, apps are closing by theirselfs, whan im on the internet my batt is empty in 10 minutes and phone always ask for connection. Im going insane whan I have to do something important with it. I have just send an e-mail to apple service in my county and i hope that they have solution for this cause i cant endure this anymore…
I found that I could still back up by right clicking on “Bryan’s iPhone” and choosing “Back Up”. After that, no more error message.
FUCK APPLE AND ITS CREATORS
I was able to fix this problem on iTunes 11 by:
1. Under “Backups”, click on “Manual Back Up and Restore/Back Up Now”
2. Use normal “Sync” button.
Thanks, I am able to fix this error now.