WD My book essential edition 2.0 Problem please help!

I have a problem and I do not know how to solve it, I used program hp usb disk storage format tool
 , and accidentally touched (WD My book essential edition 2.0) and then he divided it into two parts in a First 1.75gb while the second seems to be 489gb. The first became disk F (which is 1.75gb) and he became A (Local Disk).The second part has disappeared, I used program (easy recovery pro) and saw that  all the files are there but this part does not appear but in the program it aperd in the F disc as Unidentified.

Here is my problem.!
how Can i connect them together?

Please help the is too much important files in here Please!!!

Do not touch/ do anything to the drive as of now.

For me to help, pls answer the following:

  1. what is ur OS

  2. pls post image of Disk Management


Thanks… but no Thanks i’m done its ok now thanks again! :D :smileyvery-happy: