I've never used it once, but my understanding is that "the guest account" is there so that a Mac user can let OTHERS use the computer, while NOT being logged into the owner's account.
Can you delete the "guest" account?
I'm not sure whether it's "removable" or not.
Try deleting it, and see what happens next.
But... just "leaving it there" should hurt nothing, nor does it indicate a problem...
Have you tried:
1. Going to the users & groups pref pane
2. Clicking the lock and then entering your password, and then
3. Clicking on the "guest" account, and then
4. Making sure all the checkboxes in it are UN-checked?
... I've got people following me around and this is now another incident ...
It’s justThe "Other..." icon in the initial screenshot has an ellipsis (...). That usually indicates that the action will lead to a dialog or other screen of some kind. In the case of logins, that's probably the "Enter name and password" dialog, which doesn't display a list of users.
I suggest clicking "Other..." to find out where it leads. I recommend doing this while NOT connected to any network.
My guess is that this is nothing more than the name & password dialog, but it's been so long since I disabled the guest user that I'm not completely sure.
Also, please explain what this refers to:
It's the first time you've mentioned anything of this sort, so we have no context to interpret it.
With that screen / dialog visible, you could restart your Mac.It’s just a blank name and password field when I click “Other”