If you see one of these messages or a different message when you try to back up or restore your iOS device using iTunes, try the steps in this article to resolve the issue.
- "... the backup session failed."
- "... a session could not be started."
- "... the iPhone refused the request."
- "... an error occurred."
- "... an unknown error occurred -1."
- "... the backup could not be saved on this computer."
- "... not enough free space is available."
If iTunes for Windows stops responding or your backup never finishes, follow the steps to fix performance issues.
Copy your backup
Make a copy of a recent backup of your device and save it to your desktop or an external hard drive. You can find your backup in these folders:
|Mac OS X||
To find the ~/Library folder on OS X Lion v10.7 or later, hold the Option key and choose Go > Library.
To find the AppData folder, click the magnifying class in the upper-right corner, type
|Windows Vista or Windows 7||
To find the AppData folder, click Start, type
\Documents and Settings\(username)\Application Data\Apple Computer\MobileSync\Backup\
To find the Application Data folder, choose Start > Run. Then type
Update your software
- Get the latest version of iTunes for your computer. If you see a message that says you can't contact the software update server, follow these steps for Mac OS X or Windows.
- Install updates for your Mac. If you use a PC, you can get PC software updates from the Microsoft website.
- Install updates for your iOS software.
Restart your computer and your iOS device
After you restart your computer and iOS device, try to back up again.
Unplug your other USB devices
Keep only your iOS device, keyboard, and mouse plugged in. You need to plug your device directly into the computer.
Free up space
To back up or restore from backup, you need to free up enough space on your hard drive to store the backup or the capacity of the device.
If iTunes can't restore the device because not enough free space is available, follow these steps:
- Choose Settings > General > Reset > Erase all content and settings.
- Try to restore from the backup. You may need to restore from a smaller backup or create a new backup.
Check your security settings
You may need to update, configure, disable, or uninstall your security software.
Back up or restore using a new administrator account
If you can back up your device using a new administrator account, log in using the original user account and follow these steps:
- Make sure the account is an administrator.
- Check the permissions for the directories where iTunes writes the backup.
- Mac: Use Get Info to check the permissions on the MobileSync and Backup directory.
- PC: Contact support for your copy of Windows.
- See if there is an issue with the original backup:
- Rename the Backups folder.
- Open iTunes and try to back up again. Copy your backup before using iTunes Preferences > Devices to delete your backup.
Reset the Lockdown folder
If you can't back up as a new user, try to reset the Lockdown folder. If you reset the Lockdown folder, you may be able to start or save your backup.
- Unplug all iOS devices from your computer and quit iTunes.
- Reset the Lockdown folder.
- Plug in your iOS device.
- Open iTunes and try to back up.
Windows: Update your Intel(R) 5 series/3400 series chipset drivers
if the drivers are out of date, Intel chipsets might cause backup or restore issues. If you have one of these chipsets, you can follow the steps to fix issues syncing iOS devices with Intel Chipsets.
Back up or restore on a different computer
If you have another computer, try to back up your device from it. To restore from a different computer, copy the backup into the backup folder of the new computer. (You may need to create a Backup or MobileSync folder.)
Learn more about backups: