Screen Isue

[KenGough]

OK - my cat sat on my keyboard and pressed random keys. When I open a program the screen is a negative, i.e. the font is white on a black background rather than black font on a white background. All other functionality seems to work fine. How can I change this back? 

[Riddle_Decipher]

@KenGough It looks like your cat has enabled the high contrast mode, most probably because cats love the night, because its time for snacks, I don't know,

I'm a dog person that loves cats too, anyway, here's what you need to do, to turn it off:

Method 1:

Steps to disable High Contrast 

(keyboard shortcut in Windows 10)
 

Step 1: Press Windows button and search for - Control Panel - Select it, then open Ease of Access Center, and choose Set up High Contrast.

Step 2: In the following window, deselect Turn on or off High Contrast when left ALT + left SHIFT + PRINT SCREEN is pressed under High Contrast, and then click OK.

Method 2:

1. Right-click the Start menu and select Settings.
2. Choose Personalization from the Windows Settings menu.
3. On the left, select Themes from the sidebar.
4. Under Apply a Theme, click the link to Get more themes in the store.
5. Choose a theme, and click to open a pop-up to download it.

Let me know how that pans out,

If you feel I was helpful, simply click on Accept as Solution to help the community grow,

That said, I will have someone follow-up on this to ensure you've been helped,

Just in case you don't get back to us within 24 - 48hrs, and have a good day, ahead.