iPad 11 1ill not update to 14.7 version. error 4000

This support page makes reference to 4000-series errors:

If you see error 9, 4005, 4013 or 4014 when you restore your iOS device – Apple Support

Whilst Error #4000 is not explicitly listed in this support page, Apple Support are known to recommend that you follow these steps when troubleshooting this error - prior to seeking further assistance from Apple Support.

Apple Support can be contacted directly using the Contact Support link at top-right of this page - or by using the excellent Apple Support App. If the App is not already installed, it can be downloaded from the App Store:

https://apps.apple.com/gb/app/apple-support/id113049804

Many reports link error #4000 with AV/firewall software installed on the host PC. Whilst you do so at your own risk, you might try temporarily disabling this software in order to eliminate this as a potential cause.

You need to remove the lock on your iPhone or update through Wi-Fi.

Please see the following User Tip from our esteemed contributor Lawrence Finch for more info: https://discussions.apple.com/docs/DOC-250003773