I have been struggling with updating a clean install of Windows 8.1 on a brand new SSD (but old mobo) with KB2919355.
It appears to have finally worked.
Windows event viewer showed error 0x800F0920
I googled this and found installation issues with other KBs that were due to compatibility with audio drivers.
I noticed before the update that there was a compatibility issue with my chipset so I disabled my chipset (causing the computer to run on the windows default basic drivers).
The update appeared to have worked after that using Windows Update and using the standalone download method (I reinstalled and tried again because the computer was slow).
However, the computer is still dreadfully slow for now, right after the update. Hopefully it will speed up.
I let the computer run for awhile and then rebooted.
Both boots so far at this point have taken a long time and I had to wait at a black screen with only the cursor for a long time after logging in before the desktop appeared.
After the 1st boot, KB2919355 and the associated KBs did not show as installed in the event viewer. There were no installed updates listed in Windows Update (desktop) (not even the previous updates before KB2919355).
After the 2nd boot, KB2919355 and the associated KBs show as in the installed state in the event viewer. Windows Update (desktop) won't stop searching for installed updates, but metro version shows KB2919355 (and others) as installed. Computer is still slow
as molasses.
3rd boot: Still had to wait on the black screen after login. Still slow... The computer ran fast before updating with KB2919355.
I am leaving it on overnight... Will update if I have any progress