I just installed Linux Mint 17 and when it asked me where to install it I selected the option to overwrite the old Mint 14. Previously I had also windows with NTFS partition of 900GB. Not it is all formatted into ext4 and all the information of almost 800GB is lost.Please advise what I can do in this situation. It was light format so there should be a way to recover some of the info I have lost. Is it a good idea to format back to NTFS and try some recovery programes or something like HIREN CD?
How to recover NTFS drive formatted in ext4?
data recovery;mkfs
Well thanks @krowe. I'm on laptop so can't really use different hard drives. And this particular case was due to misleading information in the installation of Mint 17. Any way I have found a way to recover all the files i need and will drop a line here what is it all about. So first i found a live linux usb and start working from it so not to write any data on the 900GB. Then i get this nice tool testdisk. Run it with deeper search and got all the partition stuff i have lost. From there I started to recover all the files on a external HD drive.for any support on how to use the testdisk - http://forum.cgsecurity.org/phpBB3/Thanks all for the support. 