After Effects Error Asked To Create Unknown Property Of Type Fix →

Most occurrences of this error stem from older templates using obsolete expression properties or "pseudo-effects". When the JavaScript engine reads these deprecated lines, it throws an exception because the property data type no longer exists natively in the modern architecture. Run the Native Update Script

If you've recently installed or updated a plug-in, try disabling it or removing it temporarily to see if that solves the issue. Most occurrences of this error stem from older

Think of it like trying to install a car part on a vehicle that isn't designed for it—the instructions might be clear, but the underlying model just doesn't have the necessary mounting points. Understanding the "why" is the first step toward a fix. Think of it like trying to install a

If this error happens when you open a project, move the time indicator, or try to render, it is often caused by embedded Mocha data inside a layer. If this error appears immediately after running a

If this error appears immediately after running a script (like a motion graphics toolkit or a rigging tool):

A systematic approach can help you isolate and resolve the issue. Try these methods in order:

: This error frequently points to a missing third-party effect (like Magic Bullet Looks or Red Giant ). Make sure all the plugins used in your project or preset are actually installed.