Why won't Windows 10 let me set IE as default browser?

[Windows Central Question]

Windows 10 won't let me set IE as default browser

Even though I've followed the steps to set IE as my default browser in Windows 10 (Start, settings, default aps, etc.) I still get a prompt every time I click a hyperlink which reads:
How do you want to open this?
Keep using this?
Internet Explorer
-------------------------------
Microsoft Edge
other options: Look for ap in store

X Always Use This Ap
OK
------------------------------------------------------------------------------------------------
How can I get rid of this annoying prompt? I've already indicated in settings that I want IE to be my default browser...and of course everyone knows why...Edge sucks!