DOCUMENT:Q198143  02-MAY-1999  [exchange]
TITLE   :XFOR: Unique Alias Name Required for POP3/IMAP4 Client Logons
PRODUCT :Microsoft Exchange
PROD/VER:WinNT:5.5
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Exchange Server, version 5.5 
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SYMPTOMS
========

POP3 users are may not be able to log into their mailboxes. The following error
may be returned:

   The requested mailbox is not available on this server.

CAUSE
=====

The alias for each user's mailbox is the same on the mailbox propertie's general
page. Further diagnosis will show the following:

   The accounts for the clients are
   SITE1/user with an SMTP address of user@site1.org.com
   SITE2/user with an SMTP address of user@site2.org.com

Two Windows NT domains are DOM1 and DOM2, and the two Exchange Servers,
ORG/SITE1/Server1 and ORG/SITE2/Server2, respectively.

WORKAROUND
==========

To work around this problem, the Administrator needs to assign unique aliases
for every user. While the address user@site1.org.com is unique in the case of
SMTP protocol, it is not unique when a POP3 or IMAP4 client logs on. The
duplicate alias of 'user' will result in the above error.

Additional query words: ambiguous unique telnet

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Keywords          :  
Technology        : kbExchangeSearch kbExchange550 kbZNotKeyword2
Version           : WinNT:5.5
Issue type        : kbprb

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