I have a bunch of system backup files compressed using 7z with file size set in 1GB like backup.7z.001, backup.7z.002, ..., backup.7z.0??, i.e. these backup 7z files were created by 7z command:
on Ubuntu Linux so that all of these files are the 1GB breakup of 7z file. However when I tried to use PhotoRec to recover these deleted backup files, PhotoRec doesn't recognize these extensions in 001, 002, ..., 0?? during its scanning the hard drive. I also tried to create a custom signature file photorec.sig for these extensions, but it doesn't work either. My question is what is the correct format to create a custom signature file for these extensions in .001, 002, ..., and so on, so that PhotoRec can recognize these extensions when scanning the hard drive? Thanks for any clue.