According to some users on Microsoft's community forums, the recently released Patch Tuesday updates for Windows RT has broke down Windows Update, so users are no longer able to get new fixes.
"After applying the patches this Tuesday my Surface RT will not connect to Windows Update. It gets stuck on the progress circle after selecting Windows Update from PC Settings and the circle eventually stops. I can confirm this behavior on 2 of our 3 Surfaces but have not checked the 3rd yet," one user said.
"I have had the same issue - both routes to update do not work, with the desktop route actually being the least responsive. Tried restarting etc. but that has unfortunately had no effect," another users confirmed.
Source: Microsoft forums, via Softpedia