An unexpected error while signing in error 403

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Hi HenrichD,

If you are encountering an "unexpected error" with a 403 status code while signing in during the reinstallation of OS X El Capitan using the Disk Utility, there are a few things you can try:

1.Check Internet Connection:

Ensure that your Mac has a stable and active internet connection. The error might be related to a lack of connectivity during the installation process.

2.Verify Apple ID Credentials:

Double-check the Apple ID credentials you are using for the installation. Ensure that your Apple ID and password are correct.

3.Use a Different Apple ID:

If the issue persists, try using a different Apple ID. Sometimes, there might be an issue specific to your account.

4.Check System Date and Time:

Make sure that the system date and time on your Mac are set correctly. Incorrect date and time settings can sometimes cause authentication issues.

5.Clear App Store Cache:

• Open the App Store on your Mac.
• Hold down the 'Option' key and click on 'Purchased.'
• Click on 'Clear' next to 'Clear Cookies.'

6.Try Later:

Sometimes, Apple's servers may experience temporary issues. If possible, try the installation later.

7.Use a Bootable Installer:

Instead of using the Internet Recovery or Recovery HD, consider creating a bootable installer on a USB drive and installing OS X El Capitan from there.

8.Contact Apple Support:

If none of the above steps resolves the issue, it might be best to contact Apple Support for assistance. They can provide more specific guidance based on your situation.

It's worth noting that OS X El Capitan is an older operating system, and Apple's support for it may be limited. If possible, consider upgrading to a more recent macOS version for better compatibility and security updates.

Good luck!

Greetings

AntonBernad