You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

💡 Did you know?

⏺ If you can't accept iCloud Terms and Conditions... Learn more >

⏺ If you don't see your iCloud notes in the Notes app... Learn more >

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Level 1

4 points

unknown error (4000)

Hello,

I can't installing my update, the massege appears :

unknown error occurred (4000).

I tried every single step, but still occurred.

Thank you

iPhone 7, iOS 15

Posted on Apr 15, 2022 11:28 AM

Top-ranking reply

Level 10

209,067 points

Posted on Apr 15, 2022 11:42 AM

See this Apple article: If you see an error when you update or restore your iPhone, iPad, or iPod

Guess you use a Windows PC, if so check all the AV & Firewall you use on the PC.

Disable all AV & Firewalls temporarily while you restore & update your apple device.

If they are On, turn Off Hotspot & VPN.

View in context

Similar questions