Western Digital 1TB External Hard Drive Not Recognized by PC

Hello,

I have a WD 1TB external hard drive. External hard disk not recognized when plugged-in. I have Window 7 in my computer. My hard disk showing problem from few day, when I connect with my computer it would light up when plugged in, but simply stopped showing up in My Computer. I went into Computer Management and click on Disk Management a new window has open name as Initialize Disk it show two option MBR(Master Boot Record ) and GPT (GUID Partition Table ) and both option are not working. When I click any one option and press ok it show in new window name as Virtual Disk Manager and (the device is not ready) it show this message.

In the Disk Management it show Not Initialized and Unallocated. I try to connect in different pc but it showing same problem, it would light up when plugged in, but simply stopped showing up in other Computer well.
So, please give me solution.