External Hard disk not detecting in any system

This is to inform you that I have taken a western digital hard disk of 1000 GB around 8 months back. Currently I observed  that my hard disk icon is not visible on any device I used, though hard disk vibrate as usual.I showed it to western digital office but they are unable to resolve the problem. I have some important data in it. I will be highly delighted if I am able to access my data again.

Please look into the matter.Your kind support will help me a lot.

You can take it to a recovery company or recover it yourself

removing the drive from the enclosure is required in some cases, this will void the warranty