Why does Outlook launch IE in the background?

It's called "Microsoft Office Desktop Apps" in Apps & features.

Read this: https://docs.microsoft.com/en-us/DeployOffice/overview-of-update-channels-for-office-365-proplus to understand which channel you want to choose. The build for *this* issue will show in Insider first, then Monthly, then Targeted.

32 bit vs 64 bit depends on whether you have any older com-addins you need to run. If you do, you likely need 32 bit for compatibility. Otherwise 64 bit should be your default choice.

That's the Microsoft Store version of Office, which is not updated at the same frequency as Click-To-Run. You can uninstall that and go to office.com and install the Click-To-Run version.

1.  How do I uninstall the store version (Win10).  It's not in CP\ProgsAndFeatures.  [And can I rid Win10 of all traces of the store?]

2.  When I go to office.com, I eventually wind up at account.microsoft.com where my install choices are six:  32 & 64, Insider 32 & 64, Monthly Targeted 32 & 64.

Which do I want?

In spite of the additional officeclicktorun.exe process.exe, I prefer the click-to-run install.  It has less file system smoke and mirrors, and commands like "excel" work at command prompts and in start/run.

That's the Microsoft Store version of Office, which is not updated at the same frequency as Click-To-Run. You can uninstall that and go to office.com and install the Click-To-Run version.

I hadn't figured out how to include images.  I think I have it now.

I read that the lack of the "Office Updates" button was a difference between the "ClickToRun" install and the MSI install.  That seems to be borne out by my Win7 (ClickToRun) and my Win10 (MicrosoftStore) versions.  I don't get it, though, because I got them both a few weeks ago and don't recall any download/install options.

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