in exchange system management console , under email address tab of a user account there is a check box :
Automatically Update Email Address based on recipient policy.
** If I have a user that logs in to AD, but doesn't have a mailbox in Exchange, but has an external email address, would the next time the recipient policy update runs, change its email address ?
** if the user can login to AD has exchange mailbox, but has external email address as primary. Would next time the recipient update service runs, change its email address?