If they reformatted the hard disk and then re-installed Linux, and the data was kept on the disk that was reformatted, then the data is permanently lost.
If this is not the case, you should be able to find the data on the hard drive with Linux if it is still there. Try a search. Maybe it has been moved to a different location on the system.
Also make sure the data was not kept on an external hard drive, which would need to be plugged in for it to show up on the computer, obviously.
my family moved house and set up their computer at the new home. It has Linux installed. They started it up using their ubuntu disc but have lost all their data..photos etc. I am not sure why they had to reinstall ubuntu but feel this may be the problem. Can anyone help with this or is all lost.

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