[Justin Bolden]

I encountered this problem as well. Had to create an account just to share my problem and how I fixed it as it kicked my butt trying to figure it out. I tried everything that everyone suggested in this thread and none of them solved my problem.

How it all started: I created a new art board then placed an image of a cartoon character on the art board to trace. Dropped the opacity of the image down to 20% and drew a few paths. After doing so the image that I was tracing disappeared from visibility. I have no idea as to why the visibility of the image that I was tracing completely disappeared. No matter what I set the opacity to the image was not visible.

When originally placing the image that I wanted to trace a “Layer 1” was created in the layers panel. The image also appears as a sub layer. For some reason both layers container their own opacity settings and both must be at 100% for the image to appear at 100% opacity.

If you have the sub layer set to 0% opacity then the image will not appear at all even if you set Layer 1 to 100% opacity. Leave the sub layer at 100% and do all of your opacity adjusting on layer 1.

Hope this helps someone else down the road.