Try these Windows settings in order:
- Open Settings with Windows key + I.
- Go to Accessibility > Color filters.
- If Color filters is turned on, turn it Off.
- If the screen is still black and white, turn it on briefly and check whether Inverted or another filter is selected, then turn it off again.
If the screen is showing reversed colors instead of normal color:
- Go to Accessibility > Magnifier.
- If Magnifier is on, under Appearance, turn off Invert colors.
If Windows is still hard to read after that:
- Go to Personalization > Colors.
- Set Choose your mode to Dark or another preferred mode.
- If the Taskbar or Start menu looks unclear, turn off Transparency effects.
If color still does not return, check the display driver:
- Go to Settings > Windows Update and install the latest graphics driver updates, or get the latest driver from the PC manufacturer.
If the issue started after a restart and only black and white remains, the most likely cause is that a Windows color filter was enabled.
References: