cannot open movies made on avi ? Is there a fix?

Yes, .avi is legacy media and is not compatible with iMovie on Catalina.

The easiest fix is to convert the vids to Mp4/AAC with the free download, Handbrake. You can get Handbrake here:

https://handbrake.fr/

Here's another link that explains the legacy media issue and shows which formats are compatible with Catalina and which are not:

https://support.apple.com/en-au/HT209029

-- Rich

-- Rich

Hello,

Take a look at this:

https://support.apple.com/en-us/HT209029