Random hexadecimal string is added to the end of an SMTP address in an Exchange Server 2003, 2007, or 2010 environment

Consider the following scenario:
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• You have an email address policy that resembles �"First Name. Last name" in a Microsoft Exchange Server 2003, 2007, or 2010 environment.��
• You have nine mailboxes that have the same first name and the same last name. For example, you have nine mailboxes that have the first name of �John� and the last name of �Smith.�
• You try to create an additional mailbox that shares the same first and last name of the other nine mailboxes.

In this scenario, a random 4-digit or 5-digit hexadecimal string is added to the end of the SMTP address. For example, the SMTP address of the created mailbox may be John.Smith268d2@contoso.com instead of John.Smith@contoso.com.

When the Exchange proxy address engine stamps an SMTP address, it determines whether a duplicate SMTP address exists. If a duplicate SMTP address exists, the proxy address engine appends a number to the end of the SMTP address and then checks again. If there is still a duplicate for the newly appended address, the address engine increments the number by 1 and then checks again, repeating this process until there are no duplicates. However, if the address engine gets to the tenth duplicate SMTP address, it appends a 4 or 5-digit pseudo-random hexadecimal string to the end of the SMTP address.

To work around this issue, use one of the following methods:

• Change the email address policy to allow for more "unique" name creation. For example, let users include more characters from their first names.
• Provide logic in your account provisioning process to deal with the email address creation process.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.