As a login name, this is handled at the Active Directory level. Since webmaster@xxxxxxx is representing a sID, logging into a resource in another domain via local domain credentials is handled by the domain trusts. In practice, if your accounts is in abc.com domain which has a two-way kerb trust with exchange_domain.com then you acl the mailbox called webmaster with the sID represented by webmaster@xxxxxxxx At this point, webmaster@xxxxxxx does not have access to the webmaster@xxxxxxx mailbox, right? Repeat for the other domains as required. That's access. Addressing to the mailbox is straightforward with webmaster@xxxxxxx getting a mailbox (represented likely by a user object or a disabled user object in Active Directory), webmaster@xxxxxxx getting a mailbox, etc. If you're hosting, you've hopefully already read the docs describing building the GAL so that they can't see each other in the address list. Is that what you're after? Al -----Original Message----- From: A. Michael Salim [mailto:msalim@xxxxxxxxxxxx] Sent: Thursday, November 06, 2003 12:38 AM To: [ExchangeList] Subject: [exchangelist] multiple domains and login names http://www.MSExchange.org/ Hi, For those who are hosting an Exchange 2000 or 2003 server with multiple domain names, I have a question: Do user login names have to be unique across domains? If so, how would one handle several users (each with their own individual domain name) who want the same "login name" e.g. webmaster@xxxxxxx webmaster@xxxxxxx webmaster@xxxxxxx Note that these are truly independent users, unrelated to, and unaware of, one another, different companies/organizations, and *MUST* remin independent of each other. TIA! Mike. ------------------------------------------------------ List Archives: http://www.webelists.com/cgi/lyris.pl?enter=exchangelist Exchange Newsletters: http://www.msexchange.org/pages/newsletter.asp Exchange FAQ: http://www.msexchange.org/pages/larticle.asp?type=FAQ ------------------------------------------------------ Other Internet Software Marketing Sites: Leading Network Software Directory: http://www.serverfiles.com No.1 ISA Server Resource Site: http://www.isaserver.org Windows Security Resource Site: http://www.windowsecurity.com/ Network Security Library: http://www.secinf.net/ Windows 2000/NT Fax Solutions: http://www.ntfaxfaq.com ------------------------------------------------------