MSXML 4.0 Service Pack 2 (SP2) is a complete replacement of MSXML 4.0 and MSXML 4.0 Service Pack 1 (SP1). MSXML 4.0 SP2 provides a number of security and bug fixes. MSXML 4.0 SP2 does not replace MSXML 3.0.Download Microsoft XML Core Services 4.0 Service Pack 2