Windows 8.1 RT Update 3 - support.microsoft.com
Windows 8.1: Blue: August 27, 2013 October 17, 2013 (Availability) NT 6.3 Windows 8.1; Windows 8.1 Pro; Windows 8.1 Enterprise; Windows 8.1 OEM; Windows 8.1 with Bing; See Windows 8 editions. 9600 Mainstream support ended on January 9, 2018; Extended support ends on January 10, 2023; Windows 8 '8' August 1, 2012 October 26, 2012 (Availability Microsoft Ends Mainstream Support For Windows 8.1 Jan 15, 2018 Servicing stack updates (Windows 10) - Windows Deployment
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Dec 17, 2013 Latest Windows Service Packs and Updates (July 2020) Jul 01, 2020 install new windows 8.1 full version 64 bit - Microsoft
How to Install Windows RT 8.1 Update 3 on Surface RT/2
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