how to recover the lost datas from ubuntu

Restore from backup will be the easiest call by far and will give guaranteed data. If you just reinstalled and didn't read the screen then windows created and formatted a fresh partition on 100% of the disk, that's probably what happened. If you install Windows to a portion of the available space instead of the default 100% (Windows users just love hammering next) then you will avoid the need to mess around with resizing.

You could try using foremost but you will need a partition the same size as the current drive to extract the found data to, foremost will do its best but data may be damaged or totally irretrievable if data has been written over the top. You can use foremost in liveCD and access the internal drive unmounted but mount the destination as writable (Could even mount a shared location (FTP / SMB / SSHFS as writable too, that will also do).

So in short, use your backups or try foremost.

@actionparsnip
most windoze users don't make backups, because it's tedious and takes too long.
my crappy vista with 250 gig harddrive, with less than half full, takes 4-5 hours to backup and just as long to recover.

they should and it really infuriates me when people destroy their data somehow, either by reinstalling OSes and not reading the screen, or by hardware failure. If data is important it should be backed up as failures can and do appen and this sort of post takes time to fill out when it is so easy to avoid.
Why do you think companies do nightly backups? The data is valuable. If users have no value of their data then no backups is absolutely fine but if the data is needed then it should be backed up, it's that simple.

i learned long ago to save all my files on external sources such as floppies and usb drives so they don't get lost when the infamous "blue screen of death" appears.

Thanks for the replies.. Im grateful to all who answered my questions. but i still need help. What my real problem is I lost all of my data when i installed ubuntu. i was using windows 7 as my operating system. i had more than 270 gb files in my hard disk. but when i installed ubuntu my windows 7 got cracked. and all the files in my hard disk got formatted. I didn't have a backup. now im using ubuntu as my operating system. And there is nothing in my hard disk now. so i want to know how to recover the lost files from my hard disk. i am new to ubuntu. i have tried some data recovery softwares like panda data recovery. but it is not even installing in my system. from your answers i found the word called foremost. but i didn't understad it. i have downloaded it from the internet. but it shows extract. i did extract but it didn't help at all. so what i want to know is how can i recover all my lost files from my hard disk.. i will be grateful to all your replies. please help to to solve my problem.

WHy don't you have a backup? Your drive motor could have failed at ANY time, then your data would have cost THOUSANDS of dollars for professional retrievlal which is not guaranteed. Or you can spend a couple HUNDRED dollars on a cheap USB storage with guaranteed data retrieval. Where is your logic?

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