Error: We couldn’t complete the updates, Undoing changes. Don’t turn off your computer.

To check system Partition: Windows Key + X, select Disk Management. All your partition are shown here.  Hope this helps and if you need further assistance post and we will be glad to Help you.

The above opinion is mine and mine alone and doesn't necessarily reflect that of Microsoft, it's employees, or any other member of this forum.

"When we try to pick out anything by itself, we find it hitched to everything else in the Universe." -John Muir

This error may appear anytime a Windows Update fails. To investigate possible solutions, we need to start with the specific error code.

We can do this by viewing your update history.

1. Swipe in from the right edge of the screen (or, if you're using a mouse, pointing to the lower-right corner of the screen and moving the mouse pointer up), and tap or click Settings.
2. Tap or click Change PC settings, and then Update and recovery.
3. Tap or click View your update history.

View failed update error code.

Please post here with your error code, so that the Community can try to help guide you appropriately.

couldn't update to windows 8.1 Error code: 0x80007002c-0x2000D

@Robert, I definitely will be doing an image backup.  One of the things I planned to do prior to the reset of the Windows Update components is to use dism to remove KB2919355 and the 5 other fixes in the standalone package.  My suspicion is that the pending install of the previously downloaded fixes is at a minimum creating confusion and making the logs harder to interpret.  

If all else fails, I have an image backup from April 10th just when KB2919355 had been offered (selectable) via Windows Update.  I hope this backup does not already contain the root cause of my install issues.

 recommendation was to run dism.exe /online /cleanup-image /scanhealth and then dism.exe /online /cleanup-image /restorehealth to minimize the number of updates that have to downloaded.

Ask about the controversy concerning plain /restorehealth versus other kinds

C.f. 

http://answers.microsoft.com/en-us/windows/forum/windows8_1-windows_update/error-0x80073712-when-installing-kb-2919355/c5a08cdf-6e41-4b67-b2ae-68f542070840?page=2&msgId=ccb118fa-34b4-4718-8489-00b3555781b6

(contains a link to Dogtamer's post about this stuff and cites an extract from it)

Also, FWIW I still think that I have seen more positive feedback about Marek Kusmierski's script (especially with the postscript) than any other procedure.  Ask about that too.

C.f.

http://answers.microsoft.com/en-us/windows/forum/windows8_1-windows_install/kb2919355-windows-81-update-fails-800f0092-and/4d4d23a3-695a-4bd4-b340-d2ce9c75919d?page=40

Also, did they mention backup so you can undo your experiments if necessary?   <eg>

I called Microsoft at 1-866-PCSAFETY and was offered remote assistance to diagnose the problem but was cautioned that it could take 2-3 hours.  I was also offered online support through http://answerdesk.microsoft.com.  Based on my description of the situation, the person at Microsoft suggested following http://support.microsoft.com/kb/971058 and then trying the standalone installer.  I will leave Automatic Update disabled to avoid multiple updates happening at the same time.  

I also asked about the DISM procedure described at http://support.microsoft.com/kb/947821/en-us.  The recommendation was to run dism.exe /online /cleanup-image /scanhealth and then dism.exe /online /cleanup-image /restorehealth to minimize the number of updates that have to downloaded.  I will provide an update once I have had a chance to do an image backup and tried the steps above.