Windows 10 Desktop Changed to Black and White

Windows 10, 1709, fully patched.

Graphics is a nVidia GeForce 750ti.

Today while doing things entirely unrelated to drivers or graphics manipulation (I was running a command prompt, had 20 tabs open in Firefox, and that's about it), my display went from full color to monochrome. It took me a minute to notice, actually, even while I was actively working on the computer.

There were no events in the Event log that seemed to point in any particular direction.

Restarting the computer the logon screen was full color, but about 2 seconds after the desktop loaded, it all went monochrome again.

Locking the computer, the logon screen was once again monochrome, but after the screen turned off for a bit and then I wiggled the mouse and it came back, the logon screen was full color, until I logged in again.

I updated the graphics drivers to the latest (released about a week ago) to no avail.

I'm guessing it's the graphics card, but I'm interested in anyone else has experienced this and might have something else to try first.

I took a screenshot and sent it to my phone, and the screenshot itself was monochrome as well.

Why did my Windows 10 suddenly turn monochrome?

A new shortcut (Windows+Ctrl+C) was added in the Fall Creator's Update that activates colour filters and the default filter is monochrome.

The shortcut is a toggle, so pressing it again removes the filter.

Did Windows 10 suddenly turn black & white?

In Windows 10 build 16215, a new feature was added to the Ease of Access section of Windows called Color Filters. The intention was to include some features to make Windows easier to use for people with color blindness and light sensitivity. This feature can be activated and will change the color of the entire desktop display and all running applications.

The Shortcut key is Windows+Ctrl+C, which is very close to the shortcut for copying text (Ctrl+C).

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In summary, if you accidentally triggered the color filters and turned your display black & white, it's due to the new color filters feature. It can be undone by tapping Windows+Ctrl+C again.

Source Did Windows 10 suddenly turn black & white?