After the availability of XP SP3 for x86, Microsoft confirmed officially that it was the last service pack for XP. However, a potential SP3 seemed to be in the cards as far as x64 XP was concerned.
Microsoft now offered official confirmation of the fact that it was not, nor would it be in the future, developing a third service pack for 64-bit XP.
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No SP3 (Service Packs 3) for Windows XP 64-bit
