After Effects Error Asked To Create Unknown Property Of Type -

It sounds like you're referring to a where the application complains about an "unknown property of type" — often popping up when working with expressions, scripts, or linked properties.

Before jumping into fixes, it helps to diagnose the root cause. Here are the most frequent triggers:

Ask the project’s creator which version of After Effects they used. Then install that exact version (or newer). after effects error asked to create unknown property of type

Third-party plugins are the lifeblood of motion graphics, but they are also the most frequent source of this error. If you are using plugins like Element 3D, Trapcode Particular, Optical Flares, or Red Giant suites, the error often arises from:

If the error occurs during a specific action (like adjusting a slider or running an expression), use (free script) or RD: Comp Setter . It sounds like you're referring to a where

The most common trigger is a "Pseudo Effect"—a custom group of controls used in templates to make them look cleaner. If the project expects a specific version of a pseudo effect that isn't installed or is named incorrectly, this error triggers.

| Step | Action | |------|--------| | 1 | Check in the Timeline → right-click property → Copy Property Path → paste into expression/script | | 2 | Verify the property exists on that layer type (text, shape, camera, light, etc.) | | 3 | Wrap expression in a conditional: if (hasProperty) ... | | 4 | In scripts, use .valid check or try/catch blocks | | 5 | Ensure the effect is applied before referencing its properties | Then install that exact version (or newer)

: Some advanced presets use "pseudo-effects" (custom control sliders) that must be manually installed or generated by another tool before the preset will work. How to Fix "Unknown Property of Type"