Windows 10: Can't display second screen

When I go to "display settings", there is only one monitor shown. If I click "Detect", it says "Didn't detect another display".
When I do WIN +P, I see message "Your PC can't project to another screen". Try reinstalling the driver or using a different video card. What do I do?

:)

 

display problems

I was trying to hook up a second display to my pc and I accidentally clicked the option to prioritize my second display, and only show up on that display. The problem is I can't see on that second monitor to change the settings, because whenever I plug it
in my laptop screen goes black. The multiple display settings only appear when the second display is plugged I, so I cannot just unplug the display and change the settings

 

Projecting to a 2nd screen errors

By recognizes: my surface makes a sound that it's plugged in, tried to go duel screen, then makes another sound that it's disconnected. If i have the display settings open, the 2nd screen will pop up for a second then disappear. Error was that the resolution
was too high for the second screen but I can't seem to find a way to change it without being plugged in, yet it isn't recognized for enough time to change the setting of projectors resolution due to the display options closing when the second screen "disconnects"

 

OK...let's ask the obvious......do you have a second monitor?

 

What does Device Manager show for Display adapters? On a clean install and first boot to my desktop I'll get that message if I try to extend to my other two monitors. Only the basic display adapter is installed. If I wait 5 minutes of so my NVidia drivers are installed in the background. I see my monitor flicker when that happens. My display adapter then changes to NVidia GeForce GT 640 and I get full use of all three monitors.

 

I have had issues this morning, and this appears to be related to the latest update - not only is my 2nd screen "not detected" anymore, the resolution is all wrong as well. Windows installed a new driver this morning (without a reboot!) and it all went wrong there.

Some have had success by downloading drivers for their graphics card, however I have an ATI Radeon 3000, which is NOT supported anymore (and I've only had it 18 months!). So far it's looking like the only resolution is to revert back to the previous build. :-(

 

See post 9 in ATI Radeon 300 driver problem - Page 2 - Windows 10 Forums (worked for me with ATI Radeon 3000).