an unknown error occurred 4000

Hello ~ Take a look at this excellent prior post by ProustGiulio:

“If you're getting that error while updating your device via iTunes on a computer, try this workaround:

• Disconnect your device from the computer
• Temporarily disable the passcode on your iPhone
• Restart the iPhone
• Restart iTunes
• Reconnect the iPhone to your computer and restart the update procedure.

When finished, re-enable your passcode on your iPhone.”

~Katana-San~

I’m happy the solution from ProustGiulio via Katana-San solved your issue. Both of these users are excellent sources. For future reference here is a user tip with similar information→If you see Error 4000 updating your iPhon… - Apple Community

Hello ~ You are welcome. One other thing you may keep in mind for future questions…you can search the site for info as well and there are so many knowledgeable and helpful people here to learn from:)

~Katana-San~

Hello again~ One of the very knowledgeable people and very helpful is Lawrence Finch. You can always count on his information to help you. Read through the info about error 4000 to better understand issue. Enjoy updated iPhone.

~Katana-San~

Hello again~ One of the very knowledgeable people and very helpful is Lawrence Finch. You can always count on his information to help you. Read through the info about error 4000 to better understand issue. Enjoy updated iPhone. Reposting needed my glasses on:)

~Katana-San~

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