Your options for updating to Windows 8.1 depend on how you installed Windows 8.1 Preview or Windows RT 8.1 Preview. I installed the preview from the Windows Store or I installed the preview using media while Windows 8 was running ...
http://www.ebrahma.com/2013/10/updating-to-windows-8-1-or-windows-rt-8-1/Labels: 8.1, installed, RT, update-window-8, window-8, window-8.1, window-store