If you are using Microsoft Exchange 2000 Server Service Pack 3 (SP3) and you install this security update, these issues do not apply.
If you are using Microsoft Exchange Server 2003 Service Pack 1 (SP1) or Microsoft Exchange Server 2003 Service Pack 2 (SP2), click the following article number to view the article in the Microsoft Knowledge Base 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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