backup - Accidentally overwrote hard disk (with content) with a disk-to-disk image - Ask Ubuntu

i decided format laptop , reinstall again, borrowed friend's external drive had content in , downloaded disk imaging software backup hard own drive on friend's drive.

i figured software automatically created folder in destination drive, no: overwrote whole thing , content identical hard drive's - , friend's files gone...!

is possible recover friend's data?

before continue let's clear:

some data has been irrecoverably lost!

however, depending on size of data , size of friend's data, might still recoverable. e.g. if cloned small 80gb hdd onto 2tb hdd, containing 1tb of data, 80gb of 1tb lost.

if other way around, data lost.

if former, testdisk best tool, work tedious...

_{sorry, that's best can without laying our hands on hdd... :-(}