Issue with deleting a Mac account through system preferences

Question

I have a desktop mac with multiple users and I would like to erase just one user from the computer but when I open system preferences and click on the accounts area, the minus sign to delete the account is grey and cannot be clicked. I checked all the other users on the computer and they are the same way. Everything is unlocked and I have the administrator password so I shouldn't have any problems but I am unable to click the delete key. Is there another way to delete a user account without damaging the computer or any other accounts?

Answer 1

In order to add/delete accounts you have to unlock first:

which will prompt you for an Administrator account/password. Once entered successfully you can select and delete any user not currently logged in.