Resolved Three monitors: one not recognized in Display Settings

New computer, i5 9th generation processor, MSI board will support up to four monitors. We have monitors connected to the VGA, DVI and HDMI ports. The Display Port is unused. Windows 10 Home

I went to a friend's home and I'm trying to help him now over the phone since I left there. Two monitors show duplicate screens. One monitor shows different. When he goes to Display Settings, it shows only two monitors. When he clicks Detect, it says "Didn't detect another display".

What we want is to extend all the displays.

How do I get all three to show up in Display> "Rearrange your displays"?

 

Thanks, your second link described our situation precisely, even down to the VGA terminal; however, we contacted the company that built the new system and they sent a new video card that has three HDMI ports and one display port, which I installed.

After all that, the user decided to just go with two monitors and see how he likes it so we really don't know if the additional display controller would fix the problem.

I'm going to mark this thread solved because there's no "I Give Up" button.