@Gerardo,
Just an observation. I, probably like you, would be considered the admin for the office. And, it is likely safest that you do the 20 to the 20th power. But, couldn't all of the doctors go to each of the 20 computers and make the changes.
It seems like AC has answered the question. And, while, it could be easier, it is only something you would do once every few years. Just a thought.
