Hi what Red_Fox_01 ha said to you is not how it would work. If they have fogotten their password, they would have to request a password reset themselves (they need to post on the forums themselves), then wait for a senior admin to see the post and un-register them. Then when they join again they will be able to set a new password.
Red_Fox_01 Please be more careful, when posting on things which you have little knowledge of.