This error in Adobe After Effects usually appears when a script or expression tries to modify or read a property that After Effects doesn’t recognize (often due to version mismatches, corrupted workspaces, or third‑party scripts expecting a different object structure).
Below is a step‑by‑step troubleshooting guide to resolve the “asked to create unknown property of type FIX” error. This error in Adobe After Effects usually appears
If the project is under NDA or mission-critical, contact Adobe Enterprise Support. Provide them with the corrupted AEP and the exact error log from %AppData%\Adobe\After Effects\version\Logs\ (Windows) or ~/Library/Logs/Adobe/After Effects/ (Mac). Adobe Official Support If the project is under
If the error popped up but the project is still responsive, do not hit Ctrl+S (Cmd+S). Saving in a corrupted state may permanently damage the AEP file. Step 1: Do Not Save If the error
When the error first appears, do not click "OK" repeatedly. This often worsens the corruption. Instead, follow this emergency protocol:
Since this is an expression error 90% of the time, you need to find the rogue code.
EE on your keyboard (this reveals all expressions on selected layers).property("FIX"), fixValue, or strange numeric arrays.FIX, use value[0] for a simple number).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.
Ctrl+Alt+Shift+D (Windows) or Cmd+Option+Shift+D (Mac) to duplicate the current composition.