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motasem50 Author

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

Raicya

Level 10

209,307 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

If you see an error when you update or restore your iPhone, iPad, or iPod - Apple Support (SG)

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.

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unknown error (4000)

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