There is no email program associated with the requested action...

For years, I used Outlook 2007. Recently, I purchased Office 365. I continued to use both Outlook 2007 and Outlook 365. However, the other day, I started getting an error message for anything I tried to do with Outlook 2007. The message was something like: "Unable to complete operation." After researching this issue, it appeared it was nearly impossible to fix, so I uninstalled my Office/Outlook 2007, and now strictly use Office/Outlook 365. All works well, except now, I constantly get this very annoying pop-up error: "There is no email program associated to perform the requested action.... etc." I've looked for fixes, and tried several, however, the error keeps popping up. Is there a surefire way to eliminate this nuisance? Windows 10, Version 1903 (OS Build 18362.418) Thank you.

The question boils down to this: How can I get Windows 10 to recognize that Outlook 365 is my email program? This should be easy since I'm sure many, many folks with Windows 10 are using Outlook 365. Thanks

I would go to Settings>Apps>Default Apps>Set defaults by App and be sure that Outlook 365 is the default for all file type and protocol associations.

Thanks, but I don't use FF, and can' find the settings referred to in FF or Chrome (not sure what my browser has to do with this anyway). I've already set Outlook 365 as my default mail app, and the "no email program associated... " prompt continues to come up.

• I use Chrome.
• As mentioned initially, I have already uninstalled Outlook 2007.
• I have already configured Outlook 365 as my default mail app.
• The ridiculously annoying prompt not only flashes continuously in my task bar, the prompt appears in the middle of my screen no matter how many times I close it.