I have a project with a main comp, and other comps that are nexted within the main comp.
Today I opened the project, and I can see the main comp, but I can't see the content in many of the nested comps. I try to open them up, and all I see is a grey window. Where did everything go?
The nested comps are still there, and they still have all their layers. I just can't see their contents in the composition window.
Can you post a screenshot of what you are seeing?
Try changing your zoom level to "fit"