An AEP file represents an AE project definition that outlines how your video is built rather than producing a playable export, capturing compositions, Layer elements of all types, animation data such as keyframes, effect setups, masks, mattes, plus cameras and lights in 3D space, and since it usually references media instead of embedding it, the AEP stays small even when the project draws on large external assets.
Because the AEP stores links instead of embedded media, After Effects can show "offline media" if you move or rename your sources or bring only the AEP to another machine without its assets, so transferring a project normally means using Collect Files or gathering everything into one folder to keep the references intact, and if an AEP doesn’t load in After Effects, context clues—its origin, nearby files, Windows’ "Opens with," or a quick text-editor check—can help determine whether it’s genuine AE or a different program’s format.
When an AEP seems to lose its media on a different PC, the cause is almost always that it functions as a reference-based blueprint instead of a
self-contained package, with After Effects saving absolute file paths to video, images, audio, and proxy files, and when the project lands on a machine where those paths don’t match due to new drive letters, folder differences, or absent assets, AE loads the project but reports Missing/Offline Media until you reconnect the files.
A project may appear "broken" despite having the footage if the new system is missing fonts—leading to text substitution—or third-party plugins—causing effects to show as missing—or if an outdated After Effects version can’t process newer features, and the reliable remedy is to transfer via Collect Files or copy everything exactly as-is, then relink footage so that once fonts, plugins, and file paths align, the project usually resolves itself immediately.
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AEP file recovery look into our own website. An AEP file works as a lean project database that can represent a full motion-graphics project without the storage weight of footage, containing comp attributes like resolution, frame rate, length, nesting, and background, all timeline layers and their transforms such as placement values, scale, rotation, opacity, blending, track mattes, parenting, timing, plus animation instructions including keyframes, easing curves, motion blur, markers, expressions, effect parameters, and mask/roto data like outline paths, feather, expansion, and animated points.
If you enable 3D features, the AEP keeps your cameras, lights, 3D-layer properties, and render-related settings, plus organizational details like bins, label colors, footage interpretations, and sometimes proxies, but it usually leaves out the actual media—your MP4s, MOVs, images, and WAVs stay on disk—so the file mainly stores the instructions for how everything works and the paths of your source files, which is why moving or renaming footage triggers missing-media prompts until you relink.
