iTunes could not backup the iPhone because the iPhone disconnected

I am having this EXACT same problem. But I have yet to have any problem with DFU mode or anything of that matter. My iPhone is completely untouched. I've been using the 3GS cord, I have enough space on my comp, I've tried restarting my comp, erasing previous backups on iTunes, erasing backed up apps. All this effort to no avail. I have no idea what's wrong.

PLEASE HELP!

It just says, "iTunes could not backup the iPhone XXX because the iPhone disconnected" about 45min into the backup.

Your cable may be able to sync, but I would suggest to get a new cable and try. If not, you can always return it. As silly as it sounds, many people have mentioned this being the working solution.

I have that problem too ever since I updated to OS4

I just started having this problem... I backed up a week ago no problem.
I've tried everything. reset sync history, restarted mobiledevice, deleted all pics and apps since last backup, etc. Still getting errors on my main PC and laptop. It is not a corrupt backup either because my laptop has no backups and a fresh itunes install.

I can sync fine, but backup still errors "...because iphone disconnected"
I have not upgraded to IOS4. Im simply trying to get a fresh backup before my new iphone4 arrives today!

Whats the deal here?? any solutions?

Hi - has anyone managed to resolve this? I'm having the same annoying problem. I've tried four times to update to the new 4.0 software now but every time I try, I get an error message telling me that iTunes could not back up my files because the iPhone disconnects. Even though it doesn't!
It takes ages to do the back up process - around 30mins each time before it konks out.
The phone tells my 'Sync in Progress' but after a while it stops.
Can anyone help?
Thanks

Hi
I'm having the exact same problem. Ive tried a different connection lead but still the same problem.
Help

Why doesn't anyone ever actually answer these questions? Is it that hard to answer? Or is the interface between a PC and iphone just so screwed up that this happens all the time?

I like the iphone, but these stupid issues that go unresolved are very annoying. I never had this problem with the clunky Blackberry. What is the point of having a killer phone if you can't sync with your computer? and I am not shelling out $4K for a Mac!

this is just getting hopeless, been searching for answers to this problem from the web, even tried doing some of the suggested options but nothing seems to work. Even the designated iPhone distributor/service provider in our country could not offer any solutions. I hope someone from Apple could take a look into this -- and hope they'll take this seriously.

by the way, I'm using an iPhone 3Gs, updated to OS 4, but now also encountering this very annoying, persistent problem (error message when syncing).

"iTunes could not back up <iphone/device name> because iPhone disconnected"

Hello! Anyone from Apple???!!! Mr. Steve Jobs, any answers for us???

I have the same problem! I tried all solutions proposed by Apple and by other forums. I.e. 1. erasing the old backups, 2. stoping the firewall, 3. Login as different user (administrator); but nothing is working. I begin to have enough of this machine.....
Hope that Apple people reading all these posts will react immedialtelly.
Maybe it would be better for Apple to invest less in advertising and more in product testing!!!

I'VE FOUND THE SOLUTIOOOOON!!!

The antivirus is the cause of all our troubles. I disinstalled my antivirus (AVG) and know all is working fine.

Thank you Steve Jobs for the commissions you will pay to me!

Hi,

I found a solution to this problem.

I've Zapped the iTunes application, with AppZapper.
This is a Mac application that deletes iTunes + all the settings hidden on the Apple computer.

After zapping the iTunes application, I just reinstalled it and there it was.. Backup the iPhone 🙂

(no music or other media within iTunes will be deleted, just the settings...)

Link to AppZapper:
http://www.appzapper.com/

Still not fixed. Happens on Iphone 4 (os 4.2.1), and itunes 10.1

Disabling AV doesn't work, the cable and pc aren't the problem because they do everything else just fine and the problem wasn't happening with the same cable, pc and setting.

It's an itunes bug because it seems to be dependent on the number and size of the apps being synced, in my case there's over 230+ paid apps with over 10.9GB of size. It's very disappointing such a basic syncing problem hasn't been fixed after being reported for so long

Message was edited by: Hani Obaid