Not initilized,unknown

wd my passport hard disk is wont show up on my computer at all.
I went into disk management and the Disk 1 had an icon with a picture of a HD with a red arrow facing down in a white circle.
under Disk 1 it says:
Unkown
(empty line)
Not Initialized
I then right clicked and it said offline. When trying to get it back online it says:
“The system cannot find the file specified.”
In the properties under Volumes it says:
Disk: Disk 1
Type: Unknown
Status: Not Initialized
Partition style: Not Applicable
Capacity: 0MB
Unallocated space: 0MB
Reserved space: 0MB
When I try to Initialize Disk it says:I/o error

Hi prakash.lama,

It seems like the drive has gone bad. Please apply for the RMA of the drive if it is under warranty period.

You can refer to the link given below in order to know how to get an RMA to replace a defective product.