[Ben Reckelhoff]

Isolated the problem to a specific layer by adding a new comp with a white 2d circle over transparency. Moved said layer to the top of the comp and placed it over the black frame. Moved the layer down, layer-by-layer until I found where the black frame was originating. Seemed to be coming from an effect-heavy layer.

HOW I FIXED IT:
Copied all effects from the problem layer onto a new layer in a new comp and pre-composed it separately. I also cleared out all unused keyframes.
Reintegrated this precomp into the project and the black frames were gone.

Still no explanation, but some insight into a possible solution…

[Ben Reckelhoff]

SOLUTION:

Look at the file path for the missing layers (specifically where the original asset is being looked for).

Copy and paste this file path information.

Close AE without saving any changes.

Make the copied file path true.
(For me, this meant creating a new folder in my Users folder and then adding a sub-folder for ‘Downloads’ and then adding my source file.) Essentially, make AE do zero work in searching for the source file.

Reopen AE and then open your project. Your project should re-link appropriately.

[Ben Reckelhoff]

I completely understand this question. I have been working with a large illustrator file which, when imported and broken down into cropped layers (even if you intend to pre-compose immediately), consists of hundreds of AE layers. When you re-open on a different machine or HD with a new location for your source assets, there is going to be this problem. Typically, AE sorts out the file-path issues, but it seems that it can’t recognize which layers within a singe source asset to reconnect to, if there are multiple.

Strange problem, since it appears the naming scheme for the cropped layers remains unchanged and the file path only points to the single source asset, not a specific layer. It seems like some string pattern recognition could solve this pretty easily.

Sorry there’s no solution yet, but know that there are those of us that sympathize with this often unforeseen hurdle.