Suddenly Can't Use Second Monitor

[Darkroe]

I was doing a Power Point presentation for class on Zoom, using only 1 screen. I plug in my second screen after the presentation is done, it is working fine. I exit out of Power Point. Suddenly screen flickers and now I can't use my second monitor.

 

Either monitor works fine as my main monitor, but my computer cannot use both simultaneously anymore. Any idea what happened?

[Letgomyleghoe]

make sure theyre correctly configured in windows, what are your system specs?

[Darkroe]

Ryzen 5 1600

RX 580 GB

32 GB 2666MHz RAM

ASUS Crosshair VI Hero Motherboard

2 x 1 TB SSDs (1 for OS 1 for Data Storage)

 

Attached is an image: it sees the monitor but can't do anything with it now.
If the second monitor is, instead, my main monitor (ie: I unplug my other monitor and only have this second monitor plugged in) it works fine.
 

[Darkroe]

Just now, Darkroe said:

Ryzen 5 1600

RX 580 GB

32 GB 2666MHz RAM

ASUS Crosshair VI Hero Motherboard

2 x 1 TB SSDs (1 for OS 1 for Data Storage)

 

Attached is an image: it sees the monitor but can't do anything with it now.
If the second monitor is, instead, my main monitor (ie: I unplug my other monitor and only have this second monitor plugged in) it works fine.
 

Monitors are an Acer S220HQL and a Dell 1920 x 1200 monitor (whose model number I do not know)

[Letgomyleghoe]

3 minutes ago, Darkroe said:

If the second monitor is, instead, my main monitor (ie: I unplug my other monitor and only have this second monitor plugged in) it works fine.

have you tried different ports on your gpu?

[Darkroe]

5 minutes ago, Letgomyleghoe said:

have you tried different ports on your gpu?

The only port the Acer monitor uses (the one Windows can't use as a second monitor for some reason) is an HDMI port, which worked fine until the incident, and still works fine if the Acer monitor is the only one connected to my GPU

 

[Darkroe]

New report: the second monitor shows the windows icon when loading in after turning on the computer, but as soon as windows reaches the login screen, the second monitor displays nothing

[SamClan]

might be far fetched, but get another driver for your Monitor, not Graphic-card but Monitor. 

[Darkroe]

Okay I found the solution, but I have NO IDEA why it changed in the first place:
I asked Microsoft Support for help (which STRANGELY worked in this case) and the automated bot came back with something about display configuration, so I typed "display configuration reverts to one screen only windows 10" into google and was presented with the "Windows Logo Key + P" shortcut.

This leads to Windows 10's display configuration side tab where my settings were set to "PC Screen Only" for some reason. I changed it to "Extend" and VOILA! Problem solved!

 

However, I noted that in the Display Settings, whenever I have "PC Screen Only" enabled through the "Windows Logo Key + P" shortcut, the "Multiple Displays" category in "Display Settings" vanishes, and so without the "Windows Logo Key + P" shortcut, I cannot access the "Multiple Displays" settings in "Display Settings."

So it appears somehow when PowerPoint crashed, it enabled "PC Screen Only" in the "Multiple Displays" category in "Display Settings."
 

I have sent Microsoft an e-mail about it. It may just be an isolated incident, so I won't worry about it too much, but that was odd and frustrating. Thank you to everyone who made suggestions on this post.