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

I posted to this thread towards the beginning, mostly as a "me too," as I was having much the same problem with this update as everyone else...  It would install completely but then fail upon reboot and eventually undo all changes.   There was no error code and the install history showed that the update was installed even after the "undo all changes." 

On page 5?  We found out that if there was a space problem somehow it wasn't likely to be associated with a partition.   I suggested you try to get more information about your failure, e.g. with a trace.  But even just looking in the logs would probably have found something.  The problem is that these failures are mostly of a class of error known as "This will never happen."  so of course there is no simple external symptom for the user to report (especially since the recovery action for them is to try to undo things and pretend that they didn't happen) and the only way to get more details about them is to dig into the diagnostics in whatever way you can.

Then I'll be without updates until I move to another OS.  I'm not wasting hours on re-installing this same OS, with the chance, or even likelihood that MS will just screw up my system again down the road.

Ron - there's no magic fix coming that I can see.  They already released an update to this KB2919355, I don't see another version coming.

Waiting won't fix this problem.

I posted to this thread towards the beginning, mostly as a "me too," as I was having much the same problem with this update as everyone else...  It would install completely but then fail upon reboot and eventually undo all changes.   There was no error code and the install history showed that the update was installed even after the "undo all changes." 

Like so many others of you, I have tried all of the suggestions short of wiping my system and reinstalling.  This last post said "I can't help people when their systems are so corrupted that only a repair install will work."  Well I, for one, did not have any corruption on my system until this update and any corruption now has been caused either by the update itself, or by the DISM calls that Microsoft suggested to correct the problem, which haven't seemed to really help anyone.  I have been silent on the last 22 pages of this thread because, quite frankly, I have not had anything more constructive to add.  Nothing I have tried has made any difference and I have simply taken a "wait and see" approach with Microsoft, hoping that eventually they will fix the problem with this and issue a new update.  Thus far, that has not happened.  

My system continues to run fine without the update and while I know that someday soon I will stop receiving updates because of this problem, this is still less of a headache for me than actually wiping the entire system.   Clearly there are many, many of us out there with similar issues and clearly Microsoft is aware.  Hopefully a solution will be forthcoming, until then I continue to wait (and apparently in plenty of good company)...

--Ron

 I can't help people when their systems are so corrupted that only a repair install will work.

@ Susan

Did you see the one that I was working with where DISM itself was probably the problem?  Is that case being noted somewhere?  Unfortunately the poster got tired of waiting for me to try doing my reverse engineering (on a weekend) and reinstalled.  So there went that opportunity.

http://answers.microsoft.com/en-us/windows/forum/windows8_1-windows_update/issue-with-installing-updates-on-windows-81/24b91da6-fdbe-42dd-96c6-3cc91062054b?page=5#LastReply

There were many questions raised there about the implementation it would be useful to know the right answers for, instead of having to resorting to informed guessing (based mainly on comparisons with my own system).