Error: 0x80073712 when installing KB 2919355

I'm 100% there with you Ms. Bradley.  The unfortunate reality is Microsoft isn't doing it's responsibility to fix this.  Sure, they'll remotely connect to your computer, but if you don't have the 8.1 install media, they're going to tell you to reset/refresh, which is what every Microsoft employee who is a moderator has been telling users, which angers me as 1. a refresh/reset should never be done to solve a technical problem, and 2. it's blatant incompetency (such is the moderator who started this thread).

Microsoft has been aware of the system file corruption for 2 months as of this week, and they still haven't acknowledged they caused massive system file corruption within their own customers' computers to such an extent dism can't repair the massive component store corruption, nor will it fix the corruption by using the /source flag, which is extremely troubling.  I'm not exaggerating... this level of self-induced corruption is unheard of.  All the while, Microsoft is making it perfectly clear they don't care if you can't update to KB2919935 due to their massive screw up, they're going to withhold all further patches if you don't update within a little over a week (deadline had already passed, and while they did extend it by two weeks, they massively underplayed the seriousness of what they had done to their customers' computers in their press release)... which they already started, as 11 patches won't become available until a user installs KB2919355.

I absolutely agree, customers should not have to inconvenience themselves by combing software sites for an 8.1 iso from msdn that they can verify sha1 hashes with, but Microsoft is going to do very little to help users fix the corruption with an install repair.  All they would have to do is allow access to an 8.1 digital download on their site, where a user must first authenticate they have a valid windows activation, much like the old WGA when you went to download XP mode on Windows 7.  Microsoft already has the systems and accesses in place to do so and simply don't believe it's worth their time because a few thousand users don't matter when they have hundreds of millions of customers... which is sad.

I can upload my copy of 8.1 Pro x64 to OneDrive, Google Drive, or MediaFire, however many I've spoken with haven't had Pro x64.  If someone does, I'd be more than happy to upload the ISO.  

I could probably just get away with uploading the install.wim (or install.esd, as I converted mine), but someone with more knowledge than I would have to tell me if that's all that's needed.

That's a great question, seeming as the only way to gain access to an 8.1 iso was when a person upgraded from 8 to 8.1 and chose the option to save the files to usb or iso.  Since the Microsoft application that was used to upgrade from 8 to 8.1 no longer accepts valid or generic product keys, it now becomes impossible to even create a virtual machine with Hyper-V, install 8, download the Microsoft 8.1 update application and save the installation files.

While that was the easiest way to gain access to them, the other more difficult route is to run 8 from a virtual machine and use the windows store to update.  The problem is, I can't recall where Microsoft downloads the install files too... if memory serves right, it was to the user's temp files in app data - local, however I can't find the bookmark of the page that gave instructions on where to find the downloaded files at.

Seeming as Microsoft created this problem they should be the ones to make the media available to users, and while you expect malware to corrupt system files, you never dream of an OS manufacturer corrupting their own OS's system files via their own update and update software... this level of corruption is literally unheard of.  And since Microsoft refuses to give access on their site, other than subscription based MSDN or TechNet, to an 8.1 ISO, the only way to get the ISO if the user didn't take steps to when they upgraded from 8 is to download the ISO from a software forum and check the sha1 hashes to make sure the ISO hasn't been tampered with.

EDIT:

While I don't normally suggest software forums for a number of reasons, I don't agree with telling anyone they should have to wipe their system, reinstall 8, and go through the tedious hassle of reinstalling every bit of software simply because Microsoft screwed the pooch, took the cake, and ate it too.  I have little patience with Microsoft at the moment due to their idiocy of refusing to give users actual troubleshooting steps that would do something, instead of the cookie cutter response the same microsoft moderator (the one whom started this thread on page 1) gave on 4 or 5 of the 6 forum threads dedicated to the top 6 errors received from the mucked up KB2919355 install.  As far as Microsoft goes, downloading an 8.1 ISO from a software forum shouldn't be a T & C issue since Windows 8.1 is free and does not have it's own line of Activation Keys.  Since users downloading it from a Software site would be doing it to fix a windows installation that's already been activated, I would hope moderators would give a little leeway on this subject... although I also understand if none can be given.