Resetting password and reinstalling macOS on older iMac running El Capitan 10.11

I have an older iMac that I have not used in sometime. It is running an older version of MACOSX El Capitan 10.11. I have tried accessing the machine using the both the main computer login, and the individual admin users, and none of those passwords that I was aware of are working. I even had a hint built into the user accounts and all I can do is get into a Guest account.


I can use the recovery method using Command-R, and try to reinstall OSX, when I connect via my Apple ID, unexpected error 403 is the message.


I could delete the machine but that defeats the purpose of what I want to accomplish, which is take a back of the data the current iMac.


Is there a way to either reinstall a new OSX or reset the password on Both the machine and the user accounts.


Thank you



[Re-Titled by Moderator]

Original Title: Cannot Access older iMac

iMac, OS X 10.11

Posted on Nov 1, 2025 1:53 PM

Reply
1 reply

Nov 1, 2025 2:15 PM in response to ajc497

I think the "403" error indicates a problem talking to Apple's internet servers - do you have the wireless or wired internet setup on this iMac? You might be able to tell if you get logged in as the "guest" user by trying to bring up a Safari window and seeing if you can get anywhere on the web. Do you have the internet LAN cable installed between the iMac and your router?


Good luck...

Resetting password and reinstalling macOS on older iMac running El Capitan 10.11

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