Forever lost?

Media cards were dumped for future editing after a shoot. The status bars indicated all media was extracted out of the cards. Fast forward to 3 weeks later when the footage is finally up for editing and it shows as grey with zero mb (no content). What could have gone wrong? Half of the media was normal and got uploaded fine while the other half just didn't have anything at all. Is there a way to recover them? The media cards have already been used again after that shoot so they no longer have the raw files.

Any thoughts?

Hello,
If the cards wouldn't have been used since I would say you would have a chance to recover the files. But since the cards have been used there is almost no chance of recovering the files.

What happens when you dump the cards contents is this.
The files get forgotten, they still exist on the card but the OS no longer sees them. Then when new data comes along it just get written over the forgotten data, destroying it forever.

You can try some applications if you want, but the chance is very slim.
The best there is, according to some. PhotoRec - CGSecurity

I was afraid that would be the case. So the raw files were there to begin with? Because I was thinking maybe they didn't get extracted from the media cards correctly... but what's weird is that they're labeled (ie. MVI._9823.MOV; MVI._9824.MOV). It's just that there's no content.

Hard to tell, the files may have been corrupted on the card from the start or sometime durning the import process.
Unfortunately theres no way to find out for sure, if the card contents would be recoverable you could find out but now…