Inverted colours - help!

[mt12345]

My friend has following problem:
Her cat stepped on the keyboard and the colours got inverted.
Turning on magnifier then pressing CTRL+ALT+I fixes it (because it inverts colours already inverted) but if I close magnifier the colours are negative again.
What combo did the cat use???

 

[Shimshom]

Try the solution below and untick the option to invert colors if it's ticked.
How to Invert Colors on Windows 7: 7 Steps (with Pictures)

 

[mt12345]

No, it's not ticked, the colours are already inverted elsewhere. When I tick it ON it inverts it (again) so it looks normal.

 

[Arelem]

IIRC, try "Left Alt+Left Shift+PrtScn" , that's the key combo to turn on/off High Contrast screen.

 

[mt12345]

no, it's not hight contrast