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Upgrading from SharePoint Portal Server 2001?

Upgrade to SharePoint Portal Server 2003, and then upgrade to Office SharePoint Server 2007. For more information about migrating from SharePoint Portal Server 2001 to SharePoint Portal Server 2003, see SharePoint Portal Server 2003 Migration Resources (http://go.microsoft.com/fwlink/?LinkId=71516). Upgrading directly from SharePoint Portal Server 2001 is not supported.