Normally, an answer to a question can only be accepted by the asker. While votes show how many people found an answer useful, acceptance is a sign from the asker that the answer solved their problem. You should always encourage your members to accept answers when they have solved the problem they asked about.
However, there can exist a situation where a question is very important to the team, but the user who asked is no longer with the organization or has otherwise had their account deactivated. For this scenario, we provide admins of a team the ability to accept an answer, in order to help point future readers to the correct solution.
View screenshot When viewing answers to a question that was asked by a user who is now deactivated, an admin will see the checkmark as if they asked the question with a special "ADMIN" label. Clicking this checkmark with mark the answer as accepted as if the asker had done so. As with standard acceptance, it can be undone by clicking the checkmark again, or by picking a different answer to accept.