- Are it just files with text (like Notepad, MS Word and the main part of this forum) that are reverse, or also all pics that are reverse?
I'd try the graphic settings or graphic options that you reach via a right click on an empty part of the desktop, or your accessibility settings. Details depend on your OS (what version of Windows|) and your video 'card'.
Here's an example: https://www.wikihow.com/Invert-Colors-on-Your-Windows-XP
Our precocious three-year-old grandson managed to attack our Windows 7 computer keyboard and within seconds, all the files that we opened were reversed (white type on black background). The fix has to be some combination of keys because no apps were open and he couldn't have accessed any menu settings. He just hit some random keys. Any idea which combination will reset the format to normal black on white? Thanks. Bruce O.

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