It work like it should for me on windows 10. So I would guess something you have installed is causing the update to terminate abnormally. I would guess is will be a product that claims to enhance your security, or make backups as you change things.

Thanks for your thoughts but I don’t think that’s it. Here’s why. My wife uses Thunderbird on her computer and the same problem started with her at about the same time it started with me. We use our computers differently: she uses hers a little, I use mine a lot. Any installations on her computer are done by me and I don’t remember adding anything new to her computer since well before this problem showed up. But if not many people are experiencing this problem, but both computers here are having it, then it may be related to some kind of software update that happened on both our computers. I hope to hear from others who have experienced this and, hopefully, a fix. Thanks for replying.

This is not face book, where folk of a like mind get to sit together and agree. You are most unlikely to stumble on an answer by posting here, unless it is a know issue to the half a dozen regular contributors.

Personally I would point my finger at an anti virus product. Primary because they update almost hourly and are known trouble makers. See https://wiki.mozilla.org/Thunderbird:Testing:Antivirus_Related_Performance_Issues

Standard diagnostics are to diagnose problems with Thunderbird, try one of the following:

• Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled". If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.
• Restart the operating system in safe mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, OSX

If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.

On past occasions when I have looked for solutions at online help sites, I usually found that many others have had the same problem. Apparently not in this case.

Norton Security Suite runs on both computers (mine and my wife’s). Once each week I update and run a single scan of Malwarebytes on both.

Next time that Thunderbird offers to update I will say no, will stop and restart Thunderbird a few times each day, and continue this process until time for Malwarebytes. After updating Malwarebytes, I will restart Thunderbird. I am anticipating that the problem will reoccur. If that happens I will probably replace Malwarebytes with something different. If that doesn’t fix it, then I’ll try something else, probably one of the Restarts in your email.

Thank you.

You said you installed Tb 32 bit, but your system details show Win 10 64 bit. I'd be surprised if you have 32 bit Win 10, but...

So are you sure you got the right Tb package?

Next time try updating by another method instead of the popup. As Matt said, anti virus or other running programs can interfere w/ almost anything. I haven't used Windows in a long time. I don't miss it.