There may be a script that can do this project-wide, but here's a fast way to do it manually in a single comp.
Locate the search box on the timeline panel (upper-left corner, right next to the current time). Type in "casts shadows" -- all layers and properties that match will appear. Select all, then toggle from off to on.
Walter Soyka
Principal & Designer at
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Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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