what is error code 4000

Hello: You came from an excellent article. Sometimes iPhone software update failed' error can also appear if your mobile does not have enough space for the latest iOS files. Free up more storage space by deleting unwanted apps, photos, videos, cache, and junk files, etc. To remove unwanted data follow Settings > General > Storage & iCloud Usage and tap Manage Storage. Also Error 4000 means that the connection between the phone and iTunes was interrupted during a sync or an update, and other possible causes of such an interruption were not seen. There are about a dozen identified causes of an interruption, and they are all documented. If this doesn't help you go to upper right and click on Get Support.

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