WD 2TB my passport not responding

I have been using the portable hdd for last 8 months and it was ok till yesterday… I was watching a serial which was saved in my portable hdd…when suddenly the playback stopped…i ejected the drive manually as it was not responding and plugged it in again…it worked and i played the episode again , but after 1 min the same problem occured…I use windows 8 and i went to the task manager>more details>performance>disk(specific one) and saw that the percentage of load on the disk was 100% … today after i woke up whenever i just plug the hdd in , after 30 seconds the load goes to 100% and the drive becomes irresponsive…
i tried to chage the data cable and usb ports but nothing worked…

Can any one please help?? 

Hello sakib33, try running a DLG test to verify if the Passport has any hardware problems or the problem is being caused by corrupted data. Check the link below for the steps. 

How to test a drive for problems using Data Lifeguard Diagnostics for Windows 

I have been using the portable hdd for last 3 months and it was ok till yesterday… I was watching a faile which was saved in my portable hdd…when suddenly the playback stopped…i ejected the drive manually as it was not responding and plugged it in again…it worked and i played the episode again , but after 5min the same problem occured…I use windows 7 premium and i went to the task manager>more details>performance>disk(specific one) and saw that the percentage of load on the disk was 100% … , after 30 seconds the load goes to 100% and the drive becomes irresponsive…
i tried to chage the data cable and usb ports but nothing worked…

MODEL NUMBER -WDBBEP0010BBK-EESN

and i Download  Windows Data Lifeguard Diagnostics to the computer and Run the program, windlg.exe.

i tried the options for quick test and extended test.after 3 minutes message is showing lot of bad sectors and program suddenly stopped,

I dont want erase files.I need the files.

Anyone can help?