Error: 0x800F0922 when installing KB 2919355

Easy...search for 'services.msc'. Will be near the top of the list.

How and where do I find "App Readiness"?

Nevermind, I figured it out. I still can't get the updates to install.

In the end I gave up and reinstalled Windows on my laptop. This solved the issue and was probably faster than having Microsoft connect to solve the issue. of course the other plus of a full reinstall is that the machine runs quicker than before.

Therefore Windows 8.1 Update 1 is now installed and all other Windows updates seem to be working fine.

You're going to run setup from within Windows, just like you're installing a piece of software.  When upgrading, your run the installer from within windows, whereas if you're doing a clean install, you boot into the windows installation media, and run the installer outside of windows.  

Essentially, an install repair is upgrading you to the same version of windows you currently have installed.  For example, I have Win 8.1 Pro x64, so my install repair was "upgrading" my 8.1 Pro x64 to 8.1 Pro x64.  It's called a repair install and not an upgrade, other than for the obvious, because it replacing majority of the files within the Windows folder, thereby replacing corrupt system files.

***It appears I have stumbled upon a fix for all KB2919355 issues and will be posting this to numerous forum threads***

As many discoveries have been made, I discovered this accidentally. and quite by coincidence... 

In order for users, who've been plagued by errors and file corruption, to get a successful completion of KB2919355, all that's needed is to run the 8.1 upgrade installer, and when the 8.1 installed goes to the wait screen after entering the generic product key, start Windows Update for the install of KB2919355

Steps

1. Run the Windows 8.1 installer from within Windows, as if you're going to do an install repair "upgrade".
2. Enter the generic product key, and upon clicking next, the installer will say wait...
3. Give the installer about 5 minutes, then start Windows Update (it should show the KB2919355 update), and click install.
4. Windows Update will begin downloading the update... if you have a Windows Update cache problem that causes the speed and percentage to remain at zero, don't worry about it and get the update installed first, then you can clear the cache and remove the directories afterwards.
5. The install may fail, don't worry... simply hit install again, making sure the 8.1 installer screen is still on the "wait" screen, as whatever the installer is doing during the "wait" screen is what makes the KB2919355 install possible.
6. KB2919355 should install and Windows Update should request you to restart... simply do so without cancelling the 8.1 installer.  Windows will finalize the update during the shutdown and restart processes.
7. Upon rebooting into Windows, you will have a multitude of additional updates that will need to be installed (around 10, give or take a few), and you can verify the install of KB2919355 by going to "view installed updates"

A few users will need to comment back once they'e performed this in order to see if this automatically fixes the multitude of issues users are facing, and if it doesn't complete successfully, then I can back track what step I took over the past several days in order to figure out what caused this to work for me, but not others if problems occur.

What do you mean run the installer within Windows? Could you explain how to do so? I'm so sick of hearing my laptop speeding up and down over and over again.