amset

.info
.co.uk - exchange consultancy
.net - internet based solutions
Have your Exchange server installed, maintained or
upgraded by Amset IT Solutions.
Exchange 2000, 2003, 2003 SBS, 2007
More Information (UK only)

Broadband - Exchange
Login Scripts - Net Admin
Outlook - Windows Mobile
Windows

Contact - Advertise

AddThis Social Bookmark Button

Exchange Server

Exchange Consultancy


Amazon Store


Basic Email Gateway Server

Company wide Contact List

Disabled User Account

Distribution Lists

DNS Configuration

Exchange and a
Dynamic IP Address

Event ID 1221

Filter Unknown Users

Global Mailbox Folder
Permissions from Server

Intelligent Message Filter

Internal Email Address
for External People

Internet Tools

Mailbox and Management
Account

Message Tracking

Migrating to a new server

Multiple Domains

Offline Address Book Errors

Options when a Staff Member
Leaves

Outlook Web Access

PDAs, OMA and EAS

Permissions Best Practises

Post Install Configuration

Public Folders

Prerequisites for Exchange
System Tools

RPC over HTTPS

Secure your SMTP Relay

Shutdown Script

SMTP Services and Exchange

SMTP Diagnostics

Spam Cleanup

Switching From POP3
to SMTP Delivery

Telnet Test

Tools for Admin of
Exchange Server

Username Change

Exchange Server
Compatibility Information
Exchange
Server Version
Compatibility
5.5* No
2000 Yes
2003 Yes
2007 No
* May Adapt (More Information)
Two Domains, Two Users - joe @ domain1.com & joe @ domain2.com - How?

Author: Simon Butler, Exchange MVP, MCSE
Last Page Review: 09/03/2008

It is well known that Exchange can handle more than one domain. This is achieved by simply adding the extra domain to the recipient policy.
However where the problems come in is having two users (in this example both called Joe) who want joe@their domain.
If their username (on the WINDOWS domain) is joe, then Recipient Update Services (RUS) will automatically stamp joe@domain1 and joe@domain2 to the account.

Account Creation

First thing to worry about is Active Directory account creation.

Don't have either account with the user name of joe. Make them joe.smith and joe.jones as the username. If this isn't possible then ensure that the second one is called something different when setting it up.

Automatic Email Addresses

If RUS/Email Address Policy hasn't already, configure joe.smith@ and joe.jones@ as their email addresses on both domains. This will ensure that they have unique addresses. This is just a interim step.

The key point is that if you create an account with "joe" as the username then RUS will apply joe@ to all domains on the first account. If that has already happened, then you need to follow the process below so that you manually control the email address and can remove the clash. However, remember to allow time for the domain to replicate that information before trying to apply the email address removed to another account.  

Taking Control of Email Addresses

For this process to work you need to control of the email addresses.

  1. In each user, go in to the Properties, then the "Email Addresses" tab. On that tab is a selection for "Automatically updates email addresses based on recipient policy" (Exchange 2000/2003) or "Automatically update email address based on email address policy" (Exchange 2007) This should be cleared so that it isn't enabled. 
  2. Hit apply for that setting to take effect, but don't close that tab.
  3. Now change the email address to be your preferred address - including making it default or reply to address (Exchange 2007) as required.
  4. Repeat for the other user.

The end result is two separate accounts, both with joe@ as their email address.

Avoiding this Problem

There are a number of ways of avoiding this problem.

  • Don't use single names as email addresses.
    While this can be "cute" it does indicate that you are a small company. Most companies of any size will have at least one name clash.
    Instead use something like firstname.lastname which will avoid most clashes.
    Obviously there are exceptions to that - it is not uncommon for the owner to have a first name only email address, and the IT staff will also give themselves single name email address.
  • Use a different naming convention for usernames.
    If you are hosting multiple companies then create usernames that make them unique to that company.
    One example would be something along the lines of joe@trucks, joe@cars, joe@vans etc
    You could even make the username the email address!

Related Articles

Two Domains One User - How to allow a user to have two email addresses on the same Exchange server

Sponsored Links

Last Page Update:
09/03/2008

Back to the Top
Contact Us - Advertise on amset.info
Exchange Index - Home Page


Broadband - Exchange - Login Scripts - Network Admin - Outlook - Windows Mobile - Windows


© Amset IT Solutions Ltd. 1998 - 2008. All rights reserved. Reproduction of any content on this web site is prohibited without express written consent. Use of this web site is subject to our terms and conditions. All trademarks and registered trademarks are property of their respective owners. This site is not endorsed or recommended by any company or organisation mentioned on this site. This site is to provide guidance only and as such we cannot be held responsible for any consequences of following the advice given.