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http://support.apple.com/kb/ts3694#error3004
Error 1479: This error occurs when trying to contact Apple for an update or restore.
- Quit iTunes
- Disconnect from USB and restart the iOS device.
- Reconnect the device to the computer.
- Launch iTunes and attempt to update or restore again.
Error 1639: Follow these steps.Errors 3000-3999 (3004, 3013, 3018, 3164, 3194, and so on): Error codes in the 3000 range generally mean that iTunes can't contact the update server (gs.apple.com) on ports 80 or 443.
- Update to the latest version of iTunes.
- Verify the computer's date and time are accurate.
- Check that your security or firewall software isn't interfering with ports 80 or 443 or with the server gs.apple.com.
- Follow these steps to troubleshoot security software. Often, uninstalling third-party security software will resolve these errors.
- An entry in your hosts file may be redirecting requests to gs.apple.com (go to "Unable to contact the iOS software update server gs.apple.com" above).
- Internet proxy settings can cause this issue. If you're using a proxy, try again without using a proxy.
- Test restoring while connected to a known-good network.
Error 3002: If you experience this error while updating an iPod touch (2nd generation) or iPhone 3G, please use the standard update or restore process in iTunes (click Update or Restore).Error 3194: You may not have the latest version of iTunes installed. Update to the latest version of iTunes. If the issue persists, follow the steps above in "Unable to contact the iOS software update server gs.apple.com."Error 3004: If you're using a Mac, you may be able to resolve an error 3004 by quitting iTunes and using the following command in the command line: dscacheutil -flushcache.The device couldn't be restored. An internal error occurred or Error 3200: This indicates a network-connectivity or traffic issue. If you see this error, wait an hour or more and try again.Error 9807: Verify the computer's date and time.If unresolved, open access to the following VeriSign servers:
- evintl-ocsp.verisign.com
- evsecure-ocsp.verisign.com
Access to these servers may be blocked by security software, content filtering software, a misconfigured router, or anti-spyware software. For iTunes for Windows, follow these steps to troubleshoot security software issues.
Error 9808 (or -9808): Follow the steps for an unknown alert message when connectingto resolve the issue. If those steps don't resolve the issue, or if the settings revert to their original values after the restart, then follow the steps to troubleshoot security software issues.
Error 9844: This is typically caused by incorrect firewall settings. Go to "Open the proper ports and allow access to Apple servers" in the "Advanced steps" section below.