Hard drive doesn't work -- asks to format

So I have a WD My Passport Essential SE 1 TB hard drive that all of a sudden tells me it needs to be formatted.
So basically, when it is plugged in, every 10 seconds or so it disappears and then reappears with this pop-up message:
“You need to format the disk in drive E: before you can use it.
Do you want to format it?”

Obviously I don’t want to format it as that means I lose all my data.

Also, the hard drive doesn’t show on disk management.

I’m using windows 7.

By the way, I’m not really good at these, so if you have a technical solution, please give me as many detail as possible. Thank you!

The drive is probably corrupt. try some data recovery software like Rekuva which is free or tools to fix the corruption like TestDisk.