I wanted to create a bootable usb from an iso image and i accidentally put as the output of the dd, instead of my usb drive, one of my hard disks. The iso was 3,3 GB and my disk is 1TB! And it was almost full. Can i at least restore the data that has not been overwritten? Right now i can't even mount it. I get this error: Error mounting /dev/sdd1 at /media/main/UDF Volume: Command-line `mount -t "udf" -o "uhelper=udisks2,nodev,nosuid,uid=1000,gid=1000,iocharset=utf8,umask=0077" "/dev/sdd1" "/media/main/UDF Volume"' exited with non-zero exit status 32: mount: wrong fs type, bad option, bad superblock on /dev/sdd1, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so Also since i know which filesystem my disk used if i reformat it to this filesystem is there any chance i can mount it and retrieve the rest of the files?