Canon S400 Reference Manual page 230

Check 2
Is Colour Matching turned on?
The colours displayed on your display may not match the actual scanned
colours. Colour Matching attains the best match between the colours dis-
played on your display and the actual colours in the scanned image.
Color Matching can be used when the Scanning Mode is set for Color.
Windows
1
Click the Custom Setting button.
2
Make sure that Colour Matching is enabled in the Custom Setting dialogue
box.
Macintosh
1
Select Settings from the Menu screen.
2
Make sure that Colour Matching is enabled.
Image contains unexpected colors, or is too light or too dark
Troubleshooting - Scanning result is unsatisfactory 230