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Peter15,

Обычно достаточно двух: KB 2917499 и KB 2871389.

• Windows 8.1 or Windows RT 8.1 upgrade information is not displayed as expected in Windows Store
• Update is available that prepares Windows 8 and Windows RT-based computers for the update to Windows 8.1 and Windows 8.1 RT

Так же, возможно, вас заинтересует вариант How to Upgrade to Windows 8.1 Without Using the Windows Store