When Ally flags issues in a PowerPoint file, here is what each error means and how to resolve it.
Contrast Issues The presentation contains text that does not have enough contrast against the background, making it difficult to read for people with low vision, poor eyesight, or color blindness. To fix this, change the slide theme to one that provides better contrast between text and background colors.
Images Without Alternative Text Images in the slides do not have a text description. Right-click the image (or use Shift + F10), select Format Picture, open the Alt Text pane under Properties and Layout, and enter a description in the Description field. Do not use the Title field.