Windows 8 24x24 badge logo image failing wac tool test
I know this problem very well. It is not related to the image size but to the image content. The error message is actually very precise - not all pixels in your badge logo fulfill the requirement that they are fully white ##FFFFFF or transparent 00######.
I suggest your first step is a confirmation that my answer is right. For that purpose just create a temporary 24x24 image which would be completely white. If you use this temp white logo the WAC should pass.
Next step would be to get a proper logo image. I did the following with GIMP graphic tool (http://www.gimp.org/downloads/):
- Identify background color of your logo, navigate to Colors > Color to alpha and select the identified color. That makes your background transparent.
- Now it's time to desaturate the whole picture by Colors > Desaturate
- Restrict bits to ##FFFFFF and 00###### only: Navigate to Colors > Brightness-Contrast and set both Brightness and Contrast to the max values.
To be sure, I am right you might want to attach your current badge logo to your original question.