Window CHKDSK deleted all my data

Actually, while I was working and many files were open, suddenly my table fell down.
The ieexplorer.exe gave an error while outlook was still open.
Just Power Cable was removed during falling.
I re-started my computer (Forced restart, because it was not showing the start menu to shut it down manually)
When I tried to restart my computer, there was Input/output error and windows could not start even with safe mode, last known Google configuration or other
I removed the hard disk and put it on other computer.
All drives were visible, and copied some files but some gave me error "cyclic redundancy checkâ€
Guided by WikiHow for CHKDSK
http://www.wikihow.com/Fix-a-Cyclic-Redu…
The CHKDSK gave an error that it was unable to complete the disk check
When I clicked on my drive, its letter name G was changed and there was no ANY data inside
After another restart, hard disk is not visible even in "Disk Managementâ€
I have important data and will cry if I do not get it
Windows 7 64bit, 500 GB Seagate Hard Disk, fallen distance about 1 meter, available data, 121 GB
CHKDSK and further techniques tried on window XP
Need any help

 

Hi , as Arie advised run the disk drive diagnostic , which for you will be Seagate Seatools for DOS - 2 media versions of the user-created tool , a bootable a-drive diskette or iso bootable cd
These are freeware licensed for drive owners
You just create the tool from the Windows distributable file downloaded from the Seagate support site as per drive model
Connect the drive as a single hard disk drive on a known good computer in case of a virus
The tool is self booting and uses DOS operating system - so installed Windows is not required or used
Run the full test - which has a better repair component than checkdisk
Repairs will be automatic and a report generated
After repair
Test as for normal Windows boot - try all boot options , however if fails try a Linux operating system (as a recovery tool) in "try / live " mode (installs and runs from ram memory) such as Ubuntu
Using this will avoid virus or system file error issues that may inhibit your installed Windows
Windows specific viruses can not run on Linux so will boot and operate tasks uninhibited
Live /try mode does not change or over-write any hard disk drive space or data
But first remove any USB modems before booting
If the drive is mounted successfully you will have access to your personal files and be able to copy to removable media such as a USB hard disk drive or flash drive etc