cgsecurity.org

I am running Mint 15, installed the program via software manager and tried running it with each of the commands in sequence:

sudo testdisk-6.13/photorec_static
sudo: testdisk-6.13/photorec_static: command not found

sudo testdisk-6.13-lubuntu2/photorec_static
sudo: testdisk-6.13-lubuntu2/photorec_static: command not found

I tried the lubuntu variation as that is what the program is named in software manager.

Any idea how I can get this to run, having deleted a bunc of files that Picasa showed as duplicates, but which apparently were not!

Looks like your problem is related to your own computer usage...
If the program has been installed via a package manager, "sudo photorec" may suffice.
If it has been installed via an archive, use the "ls" command to list your files, "cd" to change of directory and once you have the correct program name, use sudo to run it.

Indeed, sudo photorec did it, which was not consistent with the instructions I read, live and learn!