If you are using Microsoft Exchange Server 2003 Service Pack 1 (SP1) and you install this security update, Microsoft Entourage and third-party services such as Blackberry or GoodLink may be affected. Access to shared mailboxes may also be affected. If you are using Microsoft Exchange Server 2003 Service Pack 2 (SP2) or Microsoft Exchange 2000 Server and you install this security update, these issues do not apply. If you are using Microsoft Exchange Server 2003 Service Pack 1 (SP1), review Microsoft Knowledge Base article 912918 before you install this security update.
912918 Users cannot send e-mail messages from a mobile device or from a shared mailbox in Exchange 2000 Server and in Exchange Server 2003
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