Windows 10: Cannot install anything from the Windows Store

I just recently purchased a new XBox Wireless Controller, the Bluetooth version, for use with my RetroPie setup, as well as my Windows 10 gaming rig. One of the first things I'm supposed to do is connect it to my desktop, go to the Windows Store and download XBox Accessories, then update the controller's firmware.

Well, I've tried that, and I cannot install anything from the Windows Store. I know it worked a couple of weeks ago, because I purchased Age of Empires: Definitive Edition and installed it from the Windows Store without any issues. Now, however, nothing will install. When I click on Get, the window flashes and, just for a fraction of a second, just barely long enough to be noticeable, I see a progress bar pop up, then it disappears, goes back to the main window for whatever app I happened to be looking at, and the Get button highlights again, as if nothing at all happened. I've tried several other free apps, just to make certain it wasn't only the one I wanted. Nothing will install.

I have UAC turned on, which is a requirement for installing apps from the the Store, and I've ran the Windows Store Troubleshooter. It's reset the Store app and reset my Store cache, and I've rebooted numerous times, but still nothing works.

Any ideas?

Thanks.

:)