Hello everybody,

I connected a Verbatim 1.5TB External HDD drive to a computer running windows XP (x64). For backing up purposes I simply wanted to copy the data from my computer to the external HDD. An unfortunate power cut happened while copying the data. When the electricity was back, the OP system displayed an error message: "The disk in drive F is not formatted. Do you want to format it now?" (See the picture) It shows the drive in "My Computer", though I am unable to access the drive itself. I don't want to click on "yes" to format the drive, because I have a sensitive data backed up and saved there.

Please note that the windows "Disk Management" (diskmgmt.msc) recognizes the drive, its got a letter assigned to it, but I am not able to access files saved on my external HDD from there either. I tried to connect the drive to the other home computer (running windows 7), but it gives me the exact same error message.

Is it possible that the power cut might've caused a data loss? What can I do to make it operational again? Or at least rescue the data?

Find a free recovery tool online, a few around, let it scan and choose your data you want back.

Else, get a hex viewer and carve the data out (I prefer hXD but it all works the same).

Try R-studio's demo software if it works then you can buy the software to recover the data.
http://www.data-recovery-software.net/