Windows laptop can't find T-Mobile Home Internet network... but all other devices can

I switched to T-mobile over a year ago and I’ve had to keep our old provider allllll this time, because 1 desktop PC in the house couldn’t find the gateway.  
 

All total, I probably spent a solid week’s worth of time reading these forums, doing all the stuff posted here, having support walking me through fixes (that failed), and even reading forums and support from other companies, whose users were having the same issue with those products.  
 

I even tried skipping the wireless and plugging it into the Ethernet port on the gateway, since it’s a desktop PC and not going anywhere, but those hopes were crushed when I discovered it’s in the one place in my house where the gateway couldn’t get a  signal.  
 

Last week, I was putting in a grocery order in at Walmart, not even close to thinking about technical annoyances, and I had a brain storm.  I added a USB wifi adapter to the grocery order.  When it arrived, I plugged it in, ran the setup, and BOOM! the T-mobile gateway appeared on the list.  
 

A whopping $9.99 and 5 minutes solved the problem. The desktop PC is online, its user is happy as a pig in slop, and I can FINALLY kick my old provider to the curb. 

Sometimes it pays to think outside the box, and inside the Walmart bag.  😄