Anniversary Update Failure

1. Downloaded the Windows Home update.

2. I noticed that it was at 92% of preparing the update, but later found it back at perhaps 5%.

3. Second preparation step finished, gave command to restart the computer and finish the process.

4. First step was to configure the update, which went to 100% in a single step, unlike earlier updates which always restarted the process at around 30%.

5. Computer restarted, and the installation process started working on updating (sorry, I don't recall what the actual text on the screen was.) This was quite slow, with two restarts (as the text indicated would happen.) Around 55% complete, the process speeded up, arriving at around 75% in just a few jumps, rather than percent by percent.

6. Third restart began, which sadly gave an error message that a problem had been encountered.

7 Twice, the process gathered error information and tried to fix whatever had gone wrong.

8. After the second attempt, process went into a restore of previous version of Windows; at least that worked.

This is the first update failure on this machine, dating back to purchasing it last March or thereabouts. Any ideas, suggestions, incantations that I might follow? I don't want to try downloading and going through the same lengthy process again until I have--with luck, of course--anything that might ensure success.

As an aside, I tried twice to download the Anniversary update for my wife's computer; the search for updates stated that the machine was up-to-date, which did not list the Anniversary update.

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Having received no replies, I decided to risk trying to install again. This time, the process was much faster than the first attempt; for example, the first stage did not restart, it went directly to 100% and passed matters on to step two. Unfortunately once again the install failed around 72%, but at least it then restored Windows to its previous state.

I was somewhat surprised to find, this morning, that Windows Update does not show that I have a pending update for the Anniversary release. I was further surprised that, when I checked for updates, none were offered. Given that the Anniversary update has not been installed, I wonder why it was not found during the check for updates.

Hi, you can get the iso here apparently:
Official Windows 10 Anniversary Update ISO files now available to download | Windows Central

It's a good idea to keep it or make a bootable CD or USB so you can then do an in-place upgrade repair install if necessary.

Or see here:
How to get the Windows 10 Anniversary Update | Windows Experience Blog
(Learn more)

Well, I followed one of the links I posted to launch the upgrade manually as it had not been offered via Windows update (without actually getting an iso as such though) and the update went reasonably well. Two small programs have proved incompatible - one of which was no surprise- the other is being updated, and there was a warning about an HTML editor.

The actual file downloaded was a 3Gb esd file (= electronic software distribution or some such). This is deleted during the installation process- I made a copy of it, however, during the installation.

In the tutorial section there's a small program Kari has written that supports creation of an iso from an esd file, so I'll be able to get an iso but not the way I'd thought I would.

So it didn't quite go as I had expected, but not too much to do to tidy up.

One possibility is that some installed program is incompatible. I'd forgotten to uninstall Aeroglass, but fortunately, as that prevented me logging in after the update, I could uninstall it in safe mode.

ISOs available:
Direct ISO links for the Aniniversary Update - here - Windows 10 Forums

A report which I believe I read (I'll have to check that). Great!