I think this is what you're experiencing - just came across this news article and posted it - with a possible reg fix (note caveat).
However you may prefer to uninstall the update and hide it so it doesn't recur (see Tutorial section on how).
MS admits Windows 10 Forced Update Resets Default Apps - Windows 10 Forums
....don't try to change associations from within programs- they won't 'stick'. (e.g. cab)
I would read that document, were it not that the forum says "...you do not have permission to access this page This could be due to one of several reasons:
- The page has been removed.
- Your user account may not have sufficient privileges to access this page.
- If you are a trying to post, the administrator may have disabled your account, or it may be awaiting activation."
Incidentally, the change in WinRar to allow .cab seems to have worked, as I am getting no popups for that extension, not even after installing a Critical BIOS Update from Dell. That update worked very nicely; I don't recall having ever updated the bios in my many years of PC use, but certainly remember reading many tales of woe of such matters. Equally nice, no more VLC popups, either. I am going to wait a day or so, and if all continues to be welll, shall mark this as solved, with much credit due you.
The update must have been quite critical, given that my new computer was shipped from Foxconn's massive maquiladora for Dell production in Ciudad Juarez last Thursday afternoon.
Sounds a lot better.. good..
You can't read it 'cos a moderator moved my post - whence, I know not!
This is what it said, more or less - I re-typed this for my records.
MS admits bug in KB3135173 resetting associations
See this, referring to KB3135173,
Windows 10 Forced Update Resets Default Apps To Microsoft Products - Slashdot
Updategate: Microsoft 'aware' of problem causing app defaults to reset- The Inquirer
- from which came the suggested registry modification.
Fix for "An App Default was Reset" Windows 10 Resetting File Associations (Registry Fixes) - The Winhelponline Blog
However, it would be better (I think) to uninstall the update, and hide it (see the Tutorial section)
(I basically put this in post 18 above in fact)
Given the lack of any untoward popups for over a day, I consider this problem having been solved. Now to find and fix the cause of the only continuing problem with my new computer, figuring out and eliminating the cause of its waking up. Should I not do that on my own, I shall further confound the forum members by starting a new thread.
You can only hope that a new thread shall not be required, as I shall make neither promises nor threats thereunto....
Lots of threads and ideas on PCs suffering insomnia here - another thing that seems to plague some Win 10 PCs. Hope you don't have too many disturbed nights.
I am all too well aware of the various sources, none of which, so far, have helped. -wakelast gives nothing more than a useless number; only the keyboard and mouse can wake the machine; I did not see any rogue tasks, but shall look further; and so on (and on, and on, and etc.)
This, sadly, similar to my finally finding a link that works to remove Security Essentials; I wish I had bookmarked it, so that I could provide it to others. That specific command, entered in a command prompt, immediately brought up what appeared to be a MS script or whatever it was, that, when ran, very quickly removed the nuisance.
Disturbed nights? They are something that I was once quite accustomed to, having been a fire chief.
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