An AEP file is commonly the project format for After Effects, acting as a blueprint instead of a playable video by storing compositions, various layer types, animation elements such as motion cues and expressions, effect settings, masks, mattes, plus 3D items like cameras and lights, and it generally holds only links to your source media so the file remains light despite the project relying on large external footage.

If you are you looking for more info regarding AEP file program stop by our own page. This is why After Effects may show "missing footage" when source clips are moved, renamed, or left behind after transferring only the AEP to another computer, and to avoid this you usually rely on the Collect Files feature (or manually gather the project plus all linked assets into one folder) so everything reconnects properly, and in the rare case an AEP isn’t actually from After Effects, checking where it came from, what files sit next to it, what Windows reports under "Opens with," or even skimming it in a text editor can reveal whether it’s a real AE project or a different format altogether.

When an AEP won’t show its media on another machine, it’s typically because it’s meant to point to external assets rather than include them, and After Effects stores absolute paths to footage, images, audio, and proxies, so if you move the project to a system with different directory names, drive mappings, or missing files, AE will open the project but show Missing/Offline Media until you relink the content.

A project may appear faulty 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system is missing fonts—leading to text substitution—or third-party plugins—causing effects to show as missing—or if an outdated After Effects version can’t process newer features, and the reliable remedy is to transfer via Collect Files or copy everything exactly as-is, then relink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.

An AEP file acts like a detailed structural database that holds your whole motion-graphics setup without storing footage, keeping comp details—resolution, frame rate, duration, nesting, and background—and all layers with transforms such as coordinate placement, scale, rotation, opacity, blend modes, mattes, parenting, and timing, plus keyframes, easing, motion blur, markers, and expressions, as well as full effect stacks and mask/roto information including outline data, 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 recipe for how everything works and the addresses of your source files, which is why moving or renaming footage triggers missing-media prompts until you relink.