How to proceed

[nipponvj]

Hello!
This is my first post and I would be very thankful if somebody can help me.
I have one HD with two partitions and due to power failure the system partition has malfunction.
It is a 1TB partition which was 800GB used, after the failure the OS (windows 8.1) fail to boot, after one attempt to repair from the OS with no result, I have found that the system partiton now shows only 90 gb used and most of the files are missing.
This is the result when I run TESTDRIVE on the partition affected (the other one works properly)

If I press INTEL I get this

Any idea how I should proceed?
Thanks!

[Fiona]

You shouldn't select any drive but your physically disk instead.
What's your OS?
TestDisk 32bit is recommended, if you're running windows.
Your drive is treated like a partition.
A partition doesn't have a MBR nor partition table.
That's why testdisk doesn't display your partition tabel (current partition structure) correctly.

Fiona

[nipponvj]

Thank you for your repley Fiona,
The faulty HD was running Windows 8.1, the system where I am running Testdrive is Windows 7.
I am using now Testdrive 32 and this is the result testg the logic unit.