The saved animation does not open

I was working on an animation, got halfway through it, and saved it (I’m sure of that). The next day, I wanted to continue, but it won’t open: an error occurred opening file “file name”. The animation file isn’t empty; it’s almost 40 MB. There’s a theory that Kaspersky antivirus is deleting some files from drive C — maybe temporary files or something else (I’m not really sure). I had a similar situation recently with Paint Tool Sai2: my drawing simply wouldn’t open. I’ll attach the file with the animation; maybe you can help somehow. Thank you in advance🙏🏻