DOCUMENT:Q175481 16-NOV-2001 [exchange] TITLE :XADM: Store Does Not Grow When Moving Users to Another Server PRODUCT :Microsoft Exchange PROD/VER::4.0,5.0,5.5 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Exchange Server, versions 4.0, 5.0, 5.5 - Microsoft Exchange 2000 Server ------------------------------------------------------------------------------- SUMMARY ======= When users are moved from one server in a site to another server in the same site, multiple copies of the same message are not moved to the destination server. MORE INFORMATION ================ Microsoft Exchange Server 5.5 and Microsoft Exchange 2000 Server store mail by a method that is known as single instance storage. If a message is sent to one recipient and is copied to 20 other recipients, Exchange Server 5.5 and Exchange 2000 maintain only one copy of the message in its database. It then has pointers, which point to the original recipient as well as to the 20 other recipients. If the original recipient and the 20 other recipients are moved to another server in the site with the Move Mailbox utility located on Tools menu of the Exchange Administrator program, only one copy of the message is maintained on the new server. During a move of users, Exchange Server 5.5 and Exchange 2000 checks every incoming message against its own internally assigned IDs. These internal IDs are not viewable with a client. If Exchange Server 5.5 or Exchange 2000 determines that the incoming message is a duplicate, it merely sets up a pointer for that existing message pointing to the newly moved user. Additional query words: ====================================================================== Keywords : Technology : kbExchangeSearch kbExchange500 kbExchange550 kbExchange400 kbZNotKeyword2 kbExchange2000Search kbExchange2000Serv Version : :4.0,5.0,5.5 Issue type : kbinfo ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.