I can't retrieve my files

I just got this external HD a few months ago.  I made the mistake of transferring all my pictures and deleting some of them without another backup.  I am now trying to retrieve a few and I keep on getting the error message “failed to find metadata for file”  How can I fix this?

this message indicates that the structure of the backup is corrupt, it doesn’t mean the files are lost, is just that the backup software cannot read the location of the files to copy them back to the computer. 

In this case I suggest that you  look for the files manually on the external drive so you can drag them to the computer, when you go to computer, double click on My Passport there you will see the SmartWare folder, the files are located inside of that folder.