There are three ways to reset an account's password.

Administrator methods

Re-activate the account (recommended)

These both send the user an email with a link they can use to set a new secure password

Set a new password manually

User method

Forgotten password page

This is linked to on the authentication point and at www.openathens.net:

https://login.openathens.net/auth#forgottenpassword

When used an email is sent to the user with an activation link that will let them choose a new password. This does not disable the account and access will continue to work with the old password until a new one is set. Amongst other things, this approach prevents people resetting a friend's password and disabling their access 'for a laugh'.