Windows XP Service Pack 1a was signed and released on the 29th of January 2003 at 06:49
This service pack was later replaced by Service Pack 2. You can get the SP1a xpsp1a_en_x86.exe update here. To obtain later SP packs see the XP Archive page here.
It is important to note that this release removed Microsoft Java Virtual Machine from systems as a result of a lawsuit with Sun Microsystems. Also note that if you have installed SP1 (instead of SP1a) you may have to Jump right to SP2 or SP3 depending on the OS release you installed.
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