Deleted user still shows on login screen, after logging in as guest and logging out, disappears!

As per this article : OS X: Deleted user account reappears; or, cannot use automatic login for a certain user account - Apple Support

• You remove a user from the Users & Groups pane of System Preferences, but the user account reappears the next time you open Users & Groups
• You are unable to enable automatic login for a specific user account

The user's Account Name may be the same as another user's Full Name. This situation can occur if Setup Assistant or Migration Assistant was used to migrate a user in OS X Lion, and the migrated user was renamed to have a Full Name matching an existing user's Account Name.Remove the unwanted user that has the duplicate name you don't want to keep:

1. Determine which user you would like to remove by logging in as each of the users, checking the documents found in the user's home folder, and checking to see which user-specific information is shown in various applications (Safari, Mail, Address Book, iTunes, and so forth).
2. Log in as a user that you would like to keep.
3. Open System Preferences, click Users & Groups, then click Login Options.
4. If the lock icon in the lower-left corner of the window is closed, click on it, enter an admin user's name and password, and click Unlock.
5. Click the Edit or Join button that appears to the right of "Network Account Server".
6. Click the Open Directory Utility… button.
7. If the lock icon in the lower-left corner of the window is closed, click it, enter an admin user's name and password, and click Modify Settings.
8. Click Directory Editor on the toolbar of the Directory Utility window.
9. Select Users from the "Viewing" pop-up menu (it will already be selected if the user has never used Directory Editor before).
10. Scroll through the list of users and select the Full Name of the user that you want to remove. The name you select should be identical to the name shown in the Users & Groups pane of System Preferences, for the user you want to remove.
11. Click the - (Remove) button that appears in the lower-left corner of the Directory Utility window.
12. Verify that the user selected is the user to be removed, then click the Delete button.
13. Go into the /Users folder and drag the removed user's home folder to the Trash.

Restart the machine from Apple logo and sign in with your original admin name and password make sure in users and groups your admin name is visible .

Hi Cbhuta

I'm very hesitant to offer info here, but some ideas.

First this is your login password and messing it up can make it much harder to restore.

Make sure you have current and good back-ups.

First things first, Have you done a complete shut down of your computer? This may in and of itself clear the issue.

Sounds like your key chain login password is messed up.

Look in your Keychain Access and see if the login name and password are correct and specifically see if you have 2 versions for old name/password and new name/password. If so remove the old name version.

There are ways to create a new administrator user and then reset name & password.

Here is Apple's KB on changing User Name… Change the name of your macOS user account and home folder - Apple Support

I would try to reset it again.

Finally you may have messed up ACLs and this would require using Recovery Mode and disabling SIP so not really going to give advice there.

Hope this helps, Greg

I propose a complete restart as EcoGreg already said (this empties several system and user caches).

If that does not do it: start the mac while holding the Shift key: it will start in Safe Mode (this is sloooow), login (a lot of caches are bypassed of emptied) and then choose restart from the apple menu.

Lex

🙂 Thanks !