Unluckily, http://windowsreport.com/task-host-window-windows-10/ gives 17 different possible solutions, and I'm afraid that at least 16 (and possible all 17) don't apply in your case. Moreover, most of them are explained for Windows 10. Be very careful!!
https://www.google.com/search?q=task+host+windows+7+shutdown has quite a lot of hits, going back to at least 2009, and nothing recent related to your issue. So it's a well-known problem and I doubt if it's really related to the last Windows update. It doesn't happen with me.
If you are somewhat adventurous, you might like to have a look at recent hits for Windows 7 and maybe even try them.
You can lessen the impact somewhat by not shutting down so often, but use hibernate routinely in stead of shutdown. Only shutdown to clear the sytstem when requested to restart or when something unexpected happens.
Hello Everyone,
Using W7 Ultimate; Firefox 56.0; 32bit.
Following a recent update -. which was a bit of a surprise as I thought MS had stopped all support for W7! - when I close down I am now getting a notice that I have to close the open application etc and when it shows it, it has "Task Host Window" as the cause.
I then have to click on "Force Shutdown" and then "YES" all with their respective warnings about 'losing work not saved etc'
Could someone explain what this is all about as it has only started to happen since the recent update on 11th October.
It would be nice to have reassurance that this is hot really a 'problem' and that I have to 'do' something to stop a maybe 'harmful' cause!!
Many thanks,
Regards,
Colin

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