Eureka! My computer is now up to date.
Here is the sequence (I took better notes this time):
On my update page, this is what was offered:
Definition Update for Windows Defender - KB2267602 (Definition 1.253.231.0)
Different cumulative update is being downloaded--the Sept 25th one instead of the Sept 12th one:
• 2017-09 Cumulative Update for Windows 10 Version 1703 for x64-based Systems (KB4040724)
The progress bar (which had stopped working is now showing the color bar and percentages.
It stuck at 26% progress for a long time and then at 35% the definition update was added to the list. Eventually completed to 100%.
Preparing to install updates > completed to 100%.
Then checking for updates began again.
Result: A restart is required to finish installing the following updates.
• 2017-09 Cumulative Update for Windows 10 Version 1703 for x64-based Systems (KB4040724)
After (really long) restart, the only desktop difference I noticed is that the MalwareBytes icon loaded in the tray first, even before Defender. Usually it has been the last icon to appear. I checked my MB settings to see if "self protection early start module" had been toggled on somehow, but it had not. I don't know if this is important or not, so reporting it.
This is the Update History entry after the restart:
• 2017-09 Cumulative Update for Windows 10 Version 1703 for x64-based Systems (KB4040724)
Successfully installed on 10/3/2017
Update Status: Your device is up to date.
It then spontaneously started checking for updates....apparently found none and repeated the
Your device is up to date message with current time.
If that
Media Creation Tool reinstalled Windows 10 for me, I have to say that was really a painless process and didn't seem to mess anything up. What a great tool.
Is it possible I was offered the wrong update (KB4038788) for my computer in Sept? I'm asking because one of my other failed updates turned out to not be compatible with my computer.
I have not opted into the Windows Insider updates, and I also have the business track selected which delays installation of new features until tested a while. However, after reading about the Sept 12th cumulative update, it seems it was very buggy and caused lots of problems for people. Maybe I'm glad I couldn't install it.
Is there anything more I need to do?