After Effects Error Asked To Create Unknown Property Of Type Fix Jun 2026

This comprehensive troubleshooting guide breaks down why this error occurs and provides concrete, step-by-step methods to fix it. What Causes the "Unknown Property of Type" Error?

If you are working with a Motion Graphics template (.mogrt) from Envato or Adobe Stock:

: Missing or un-updated third-party plug-ins like Magic Bullet Looks or Video Copilot's Saber.

If the project file itself is slightly corrupted, you can often bypass the error by importing it into a fresh workspace rather than opening it directly. Open After Effects and create a brand new project. Go to File > Import > File. Select the problematic .aep file.