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Windows XP Service Pack 1a (SP1a)

By Microsoft Free

Developer's Description

If you are not running Windows XP SP1, install SP1a for security and reliability updates to the Windows XP family of operating systems. There is no benefit to installing SP1a if you are already running Windows XP SP1.
We do not recommend that you install SP1a if you are already running SP1. Windows XP SP1a is almost identical to Windows XP SP1 except that the Microsoft virtual machine (VM) is removed in SP1a.

Full Specifications

What's new in version 1a

General

Release November 18, 2008
Date Added September 9, 2002
Version 1a

Operating Systems

Operating Systems Windows, Windows XP
Additional Requirements None

Popularity

Total Downloads 3,015,788
Downloads Last Week 18
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