Some users attempting to update to iOS 4.1 have reported problems updating, including errors that cancel the update another issue in which the update stalls partway through.
Restore instead of update. Backup your iPhone, then perform a restore process instead of using the check for update function. This may allow the iPhone to successfully receive the iOS 4.1 update, after which sync processes should occur at normal speed.
Switch USB ports. Try switching your iPhone to a different USB port. In particular, if you are using a hub or other intermediary device, try connecting the device directly to your computer.
Disable network connection. In some cases, simply disabling your network connection (turning off AirPort or unplugging your Ethernet cable) right after you click the update button will resolve the slow or stuck backup phase. It appears that iTunes performs some data network data transfer during the backup process which can, for unknown reasons, take an extremely long time or become stalled.
Delete backup folder. If you are using a Mac, navigate to (your username)/Library/Application Support/MobileSync/Backup/ and delete the most recent backup folder.
If you are using Windows, delete the most recent backup folder from C:\Documents and Settings\Application Data\Apple Computer\MobileSync\Backup\.
Disable antivirus software. If you are using Windows, try temporarily disabling antivirus software before applying the update.
September 9, 2010 at 4:32 AM
I had this problem also, and fixed it by going to the users/yourusername/library/itunes/iPhoneSoftwareUpdates/ folder and deleting all the .ipsw files. This causes iTunes to redownload the update file and that fixed my problem.
September 9, 2010 at 11:15 AM
I’ve had a similar issue with iTunes. Ever since i bought the new Mac mini and tried updating both my 3GS and 4, iTunes gets stuck about 3 quarters through install and does nothing. I have to restart my Mac and unplug iphone’s.
I haven’t tried a re-install of my mac’s os yet but I think I’m just about had it and will this weekend.
I’ve tried different USB ports and turning off network settings but no luck.
Hopefully a OS re-install will help my Mac and then work on restore of my iphone’s.
September 9, 2010 at 11:36 AM
I tried all of these options and the backup would hang. I finally got it upgraded by doing the “restore” option. This was from IOS 3.1.12 to 4.1 on an iPhone 3G.
September 9, 2010 at 7:11 PM
Hi, i tried all of this in mi iPhone 3G, but nothing works. It’s stuck on DFU mode and don’t start. Any other idea? Please. I have no phone.
September 10, 2010 at 7:00 AM
Like Mike, I also had to use the “restore” option to get my 3G from 3.1.xx to 4.1. I was a little wary, having never done a restore before, but it worked great on both my mine and my wife’s phone. Just make sure you do a full sync and backup beforehand (and probably wouldn’t hurt to make sure all your apps are updated in iTunes).
Our phones run MUCH smoother now than they did under 3.1, which I certainly didn’t expect. I imagine some of this is from the upgraded iOS, and some is from cleaning things up with the restore. Either way, very pleased.
September 11, 2010 at 9:52 AM
Doing the restore worked for me too. I had a bad iTunes 10 install that then jacked my phone, but after downgrading to 9.2.1 the restore and then restoring from backup worked great.
September 15, 2010 at 5:11 PM
I tried all of the above and still had no joy. However, after that, I followed Ed’s instructions to delete the .ipsw files and my phone is now working fine.
Thanks Ed, I owe you one.
September 18, 2010 at 2:21 AM
deleting the backup directory worked for me (PC) – thanks!
September 22, 2010 at 2:46 PM
Um ya same thing im trying a restore hope it works
October 4, 2010 at 12:52 AM
Thanks ED! FINALLY got mine to install update, by deleting the backup x
October 10, 2010 at 7:01 AM
I had a jailbroken iphone 3gs 16gb on 4.0.1 then i wanted to restore to 4.1 (OF).so i downloaded it from a website and then pressed alt and selected the downloaded firmware.about three quater way through the update stopped and nothing has worked can some one help me please!!!
October 12, 2010 at 5:35 PM
Tried another computer and it worked 4 me
October 21, 2010 at 11:17 AM
I am still trying to update my iphone to 4.1, but every time I click “update software” when syncing the phone (from the device menu, mind you) a pop-up message informs me that I have the current version of I-tunes. I don’t want to update I-tunes, I want to update my phone! Am I missing something? I tried restoring, which didn’t work. I’m wondering if my itunes was installed correctly…
October 28, 2010 at 10:05 PM
Restore instead of update worked for me on my iphone 3.1.2 thanks, be sure to manual back up and sink first and restore from last back up
October 29, 2010 at 4:25 PM
This could be caused by changing your Windows default file directory. Once I reverted Windows NT to the default directory in My Documents, I could do my backup and install 4.1! At last! The options above didn’t work for me (though I didn’t try a different computer).
November 28, 2010 at 10:39 AM
I tired the restore thing and it gives me an error message. Now my phone is useless. On the screen it tells me I have to hook to iTunes but I have no idea what to do from there.
December 4, 2010 at 6:08 PM
Thanks! I tried deleting the ipsw files first and no-avail. The restore worked, had to re-sync music, apps, contacts, and rename afterwards. But it works!