"asked to create unknown property of type" in Adobe After Effects typically occurs when the software encounters a script, preset, or template that references a property or "pseudo-effect" it doesn't recognize or can't access. Common Causes & Fixes Missing Plugins or Presets

: This often happens when you try to apply a preset that requires a specific third-party plugin you haven't installed (e.g., Red Giant Universe or Boris FX).

: Ensure all required plugins are installed and updated. If the preset came with a tutorial or documentation, double-check for "pseudo-effects" you were supposed to install first. Outdated Expressions

: Templates created in older versions of AE may use code that is no longer supported by the modern JavaScript engine. File > Scripts > Update Legacy Expressions.jsx

to let After Effects attempt to update the code automatically. Corrupt Preference Files

: Corrupted background settings can prevent AE from loading properties correctly. : Reset preferences by holding Ctrl+Alt+Shift (Windows) or Cmd+Opt+Shift (Mac) while launching After Effects. Extension Boot Issues

: If you use extensions like Mt. Mograph Motion v4, the error may stem from a failed initial boot of that panel. : Close the extension panel (right-click the title and hit Close Panel ) and then reopen it via Window > Extensions Script UI Conflicts

: A specific script running in the background may be the "troublemaker". : Temporarily remove files from the Scripts/ScriptUI Panels

folder, then add them back one by one to identify the one causing the error. General Troubleshooting Steps Purge Cache Edit > Purge > All Memory & Disk Cache to clear potentially corrupt temporary files. Import into New Project : Create a brand new project file and then go to File > Import > File

to bring your old project into it. This can sometimes bypass project-level corruption. Change Expression Engine File > Project Settings > Expressions , try switching the "Expressions Engine" to Legacy ExtendScript Error: asked to created unknown property of type "x" (1d16)

This error typically occurs when After Effects encounters a pseudo-effect (custom effect controls) or a Master Property

it does not recognize, often due to a mismatch between software versions, missing plugins, or conflicting font/layer names Immediate Fixes Update Legacy Expressions: File > Scripts > Update Legacy Expressions

. This can resolve errors caused by older project files using outdated JavaScript syntax. Check for Missing Plugins:

Ensure any third-party plugins (like Boris FX or Mt. Mograph) used in the project are installed and up-to-date. Rename Problematic Items: Avoid using system-reserved words like "Menu Type"

in custom pseudo-effects or Master Properties, as these can cause structural conflicts. Advanced Troubleshooting Isolate the Culprit:

Turn off layer visibility one by one to see when the error stops. Remove custom scripts from the ScriptUI Panels

folder (found in the AE installation directory) and add them back one at a time to find the "troublemaker". Clear User Presets: Navigate to ~/Documents/Adobe/After Effects [Version]/User Presets

and temporarily move the contents elsewhere. Corrupted variations of plugins can trigger this dialogue. Fix Font Conflicts: Unsync and resync Adobe Fonts

or reinstall third-party fonts used in the project, especially if they are variable fonts. Reset Preferences: Launch After Effects while holding Ctrl+Alt+Shift (Windows) or Command+Option+Shift (Mac) to delete the preferences file. Import into a New Project: Create a brand new file and use File > Import > File

to bring your existing project into it. This often bypasses corrupted project settings. Are you seeing this error at startup or when clicking a specific layer in an existing project? asked to create unknown property of type - Adobe Community

The After Effects error "asked to create unknown property of type" (often followed by "Pseudo") typically occurs when the software encounters a project, template, or preset that uses a custom effect (pseudo-effect) or a plugin that is not currently installed or is outdated. How to Fix the Error Update Legacy Expressions

If you are using an older template in a newer version of After Effects, Adobe's internal changes may cause conflicts.

Action: Go to File > Scripts > Update Legacy Expressions.jsx. This can often resolve issues where expressions are trying to call properties that have changed in newer software versions. Identify and Reinstall Missing Plugins/Presets

This error is frequently linked to specific third-party tools like Magic Bullet Looks or custom Master Properties/Dropdown Controls.

Action: If the project was created on another machine, ensure all third-party plugins used in that project are installed on your current system. Import into a New Project

If the project file itself is corrupted or stuck in a loop, importing it as a piece of footage into a fresh project can bypass the launch error.

Action: Open a new, blank AE project, then go to File > Import > File and select your problematic .aep file. Remove Conflict-Causing Scripts Some scripts loaded at startup can trigger this error.

Action: Temporarily move scripts out of your ScriptUI Panels folder to see if the error persists. You can find this folder in the Adobe After Effects installation directory under Support Files/Scripts/ScriptUI Panels. Rename Conflicting Pseudo-Properties

If you are the one creating the preset, ensure that the names in your pseudo-effect do not conflict with After Effects' internal naming structure (e.g., avoid using general terms like "Layer" as a custom property name). Drafting a Feature: "Property Resolver"

To prevent this in the future, a "Property Resolver" feature could be proposed to Adobe:

Automatic Dependency Check: Upon opening, the system would scan for all custom pseudo-effects and prompt a download/link for missing ones.

Property Mapping Tool: If a property is "unknown," a UI window would allow the user to manually map that legacy property to a new or existing one, rather than just throwing an error and resetting the project.

Safe-Mode Opening: A dedicated "Safe Open" that strips all non-native effects to allow project recovery without crashing. If you'd like to try a specific fix, let me know:

Did this happen when opening a template or creating your own preset? Are you using any third-party plugins? Which version of After Effects are you currently running? asked to create unknown property of type - Adobe Community

C. Update or Reinstall

Solution 5: The "New Project" Salvage

If the error is locked to a specific project file:

  1. Create a New Project.
  2. In the old project, select your compositions one by one.
  3. Right-click > Reduce Project (optional) or simply drag the compositions into the new project.
  4. This forces After Effects to re-evaluate the property links and often bypasses the corruption causing the "unknown property" error.

Note: If the error message includes a specific property name (e.g., "unknown property of type 'Mask Feather'"), use that clue to inspect your project for that specific property. Deleting and re-creating that specific property (e.g., removing a mask and drawing a new one) often resolves the issue immediately.

Sounds like you hit the After Effects error: "Asked to create unknown property of type 'Fix'" (or similar). That usually happens when a project references a plugin, effect, or expression that AE can't recognize. Steps to diagnose and fix:

  1. Identify the offending layer/effect

    • Open the Composition and solo layers one-by-one to find which layer triggers the error.
    • If error appears on project open, import the file into a new project and check the most recently added items.

  2. Check installed third‑party plugins

    • Common cause: missing or incompatible third‑party effect (e.g., old/freeze-frame/fix-type plugins).
    • In Effects > Install Location, verify the plugin is present (Windows: Program Files\Adobe\Common\Plug-ins; macOS: /Library/Application Support/Adobe/Plug-Ins/).
    • Reinstall/update suspected plugins to a version compatible with your AE version.

  3. Inspect expressions and JSON/Essential Graphics

    • Open the layer’s properties (press U or UU) and look for expressions referencing a property type or plugin name "Fix" or custom property creation.
    • If expressions reference external scripts or CEP/ExtendScript panels, ensure those scripts are available and compatible.
    • If error appears when using Essential Graphics or JSON-based templates, the exported template may reference a custom property type not recognized by current AE; re-export from the original AE version or remove the custom property.

  4. Check project/asset compatibility

    • If project was created in a newer AE build or with a beta, open it in the same/newer version. Backwards incompatibility can produce unknown property types.
    • Try File > Dependencies > Collect Files and open the collected project on the original machine/version if possible.

  5. Remove or replace the bad property

    • If you locate the property in the Timeline, right-click and remove the effect/property or disable expression.
    • Replace with a native AE effect or an up-to-date plugin alternative.

  6. Safe troubleshooting steps

    • Reset AE preferences (hold Ctrl+Alt+Shift / Cmd+Opt+Shift on launch) — saves time but loses custom prefs.
    • Purge memory & disk cache (Edit > Purge) and restart AE.
    • Create a new comp and copy layers incrementally to isolate the problematic item.

  7. If the error persists

    • Export a minimal reproduction: the smallest project that reproduces the error.
    • Search/update or remove any scripts, expressions, or exported Motion Graphics templates (.mogrt) used.
    • If from a template purchased/downloaded, contact the author for an AE-version-compatible update.

If you want, paste the exact error message, AE version, OS, and list of installed third‑party plugins (or attach the small problematic project). I can give targeted steps for that setup.

Related search terms I can generate next: "After Effects 'unknown property of type' error", "Asked to create unknown property of type Fix After Effects", "After Effects plugin compatibility Fix property".

The Bottom Line

The "asked to create unknown property of type FIX" error sounds technical and scary, but it is rarely a system failure. It is simply language barrier between an old script or corrupted expression and your current version of After Effects.

Find the expression, kill the weird code, or re-build the master property. You'll be back to keyframing in less than five minutes.

Have you encountered this error before? Did a specific plugin cause it? Let me know in the comments below!

Happy animating, and may your previews be green.

The "asked to create unknown property of type" error in Adobe After Effects typically occurs when the software encounters a missing plugin, an incompatible preset, or a bugged script that references a property After Effects doesn't recognize Common Causes Missing Third-Party Plugins:

Opening a project that uses effects from plugins you don't have installed (e.g., Boris FX BCC, Red Giant Universe). Pseudo-Effects & Presets:

Applying a preset that relies on a "pseudo-effect" (custom-coded controls) that hasn't been properly initialised or created in your version of After Effects. Legacy Expressions:

Using older project files or templates with expressions built for older versions of the After Effects Javascript engine. Essential Graphics/Master Properties:

A known bug where using dropdown menu controls in master properties can trigger this error during startup. How to Fix Error: asked to created unknown property of type "x" (1d16) 21 Jun 2022 —

The "After Effects error: asked to create unknown property of type" typically points to missing plugins, corrupted preferences, or legacy expression conflicts. This often occurs when opening project templates or presets designed with third-party tools that aren't currently installed. Common Fixes

Install Missing Plugins: This error often occurs when a project uses a specific effect—such as Red Giant Universe—that is not installed on your system. Identify which effect is missing and install it.

Update Legacy Expressions: If you are using an older project template, the expressions may be outdated. Go to File > Scripts > Update Legacy Expressions.jsx to automatically update them for newer versions of After Effects.

Remove Problematic Scripts: A script running at startup might be the "troublemaker".

Navigate to the ScriptUI Panels folder (typically found in Support Files/Scripts/ScriptUI Panels on Windows or Applications/Adobe After Effects/Scripts/ScriptUI Panels on macOS).

Remove scripts one by one to identify which one causes the error.

Reset Preferences: Corrupted preference files can cause unexpected property errors. Reset them by holding Ctrl+Alt+Shift (Windows) or Command+Option+Shift (macOS) while launching After Effects.

Change Expression Engine: If the error is expression-related, try switching engines. Go to File > Project Settings > Expressions and change the engine to Legacy ExtendScript.

Check for Pseudo-Effects: The error may refer to a "pseudo-effect" that needs to be manually created or applied via a specific preset first. Quick Maintenance Steps

The "After Effects error: asked to create unknown property of type" is a common but frustrating warning that typically indicates a mismatch between the software and the project's scripts, expressions, or plugins. This error often occurs when After Effects encounters a "pseudo-effect" or a custom property it doesn't recognize Common Causes Outdated Expressions

: Projects or templates created in older versions of After Effects may use expressions that the modern JavaScript engine cannot interpret. Missing or Outdated Plugins : If a project uses third-party tools like Boris FX Continuum Red Giant Universe

that are not installed or are an incompatible version, After Effects may fail to create the required properties. Third-Party Scripts : Conflict with ScriptUI panels

or scripts running in the background can trigger this error during startup. Corrupt Preferences

: Internal configuration files can sometimes become corrupted, leading to "unknown exception" warnings. How to Fix the Error 1. Update Legacy Expressions

If the error is caused by an old template, you can often fix it by converting the expressions to the modern engine: File > Scripts > Update Legacy Expressions.jsx Alternatively, go to File > Project Settings > Expressions and change the Expressions Engine to Legacy ExtendScript 2. Troubleshoot Scripts and Plugins Isolate Scripts : Remove scripts from the ScriptUI Panels

folder (located in your Adobe After Effects installation directory) and re-add them one by one to find the "troublemaker". Check Plugins

: Ensure all third-party plugins used in the project are updated to their latest versions. If a specific plugin is mentioned in the error (e.g., BCC), try reinstalling that package. GPU Acceleration

: Sometimes conflicts with the GPU can cause property errors. Try switching your renderer to Mercury Software Only File > Project Settings > Video Rendering and Effects

FAQ: How to fix "Unknown BIB Error" in After Effects | Community

After Effects Error: Asked to Create Unknown Property of Type - FIX

Are you experiencing the frustrating "Asked to Create Unknown Property of Type" error in Adobe After Effects? This error can occur when you're trying to access or modify a property that doesn't exist or is not recognized by the software. In this article, we'll explore the causes of this error and provide step-by-step solutions to help you fix it.

What is the "Asked to Create Unknown Property of Type" Error?

The "Asked to Create Unknown Property of Type" error typically occurs when you're working with expressions, scripts, or plugins in After Effects. It's a generic error message that doesn't provide much information about the root cause of the issue. However, it usually indicates that there's a problem with a specific property or attribute that you're trying to access or modify.

Causes of the Error

There are several reasons why you might encounter the "Asked to Create Unknown Property of Type" error in After Effects:

  1. Outdated or corrupted plugins: If you're using outdated or corrupted plugins, they might not be compatible with the latest version of After Effects, leading to this error.
  2. Incorrect expression syntax: Expressions are a powerful tool in After Effects, but if the syntax is incorrect, it can cause errors.
  3. Missing or renamed properties: If a property is missing or has been renamed, After Effects might not recognize it, resulting in this error.
  4. Scripting errors: Scripts can also cause this error if they're not written correctly or are trying to access non-existent properties.
  5. Version compatibility issues: If you're working with projects created in older versions of After Effects, you might encounter compatibility issues that lead to this error.

Solutions to Fix the Error

Now that we've covered the causes of the error, let's dive into the solutions:

4. Check for Corrupted Files or Project

Solution 3: Purge All Memory & Disk Cache

Sometimes cached frames or internal data structures cause property conflicts.

  1. Open After Effects.
  2. Go to Edit > Purge > All Memory & Disk Cache.
  3. Restart the application.

3. Close Other Applications

Other applications running in the background might interfere with After Effects, especially if they're using a lot of system resources or interacting with similar file types. Try closing other apps and see if that resolves the issue.