Forgot my administrator password

https://support.apple.com/en-us/HT202860

How to change the admin password on a Mac…

https://www.macworld.co.uk/how-to/mac-software/change-admin-password-mac-3535328/

You can create a new administrator account by restarting the Setup Assistant:

1. Boot into Single User Mode: Start/restart your Mac. As soon as you hear the startup tone, press and hold ⌘ + S until you see a black screen with white lettering. (If you end up back on the login screen after a flash of the black screen with white lettering, enter your password and it will return to the black screen.)
2. Check and repair the drive by typing /sbin/fsck -fy then ↩ enter - as directed by the on-screen text.
3. Mount the drive as read-write by typing /sbin/mount -uw / then ↩ enter.
4. Remove the Apple Setup Done file by typing rm /var/db/.AppleSetupDone then ↩ enter.
5. Reboot by typing reboot then ↩ enter.
6. Complete the setup process, creating a new admin account.

Be very careful to notice the spaces in those Terminal Commands.

Once you've done that the computer reboots and it's like the first time you used the machine, except all your data will stile there. Your old accounts are all safe. From there you just change all other account passwords in the account preferences!!

I forgot my administrative password and have been trying to change but it will not allow me to do it. I usually write these things down in a book I keep but there was no password. How do I fix this?

I need to reset the administrator password for my iMac?

I need to reset administrator password because I forgot the old password

Did you try my solution above?

Or, Reset your Mac login password…

https://support.apple.com/guide/mac-help/reset-your-mac-login-password-mh35902/mac

Sorry, didn't understand how this worked. looking for answer to same question as lionel64

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