AVHD video file wont open. Error (1718449215)

Hey, Apple? Nobody cares in Apple care?
I have exactly the same problem. Before this i received a message about audio unit and permissions and lowering the security level, i answered "yes" but I get the message: The document “BDMV” could not be opened. An unknown error occurred (1718449215)

Do something, otherwise my masterpieces will never become the heritage of mankind...

I have the same problem. I just updated to 10.13.3 and now I can not import to Final Cut or open AVHD files in Quicktime. I get the same error code, 1718449215.

That helps me ! Here we go

Unable to import AVCHD (BMDV) movies to photos app since High Sierra update

I went back to Sierra, nothing else to do ...