I Have Ego Portable Hard Drive From Iomega And It Has Problem

My 500 GB hard drive contains my stuffs like movies, documents etc. some of them are important for me. Recently i got some problem in my hard drive. they are described in three parts as below:1) My Iomega drive was detected by my computer on and off. I could see some time its content and some time no2) i gave my hard drive to a local computer mechanic. he ran a software to recover the data and it took a long time and he said hard disk could not be recognized3) now when i connect my hard drive, my computer can recognize it with a light indicator on my hard drive and a distinct sound of USB device inserted but now, I can not see the hard drive letter on the computer and hence can not see the content of it. It does not make any sound if i tried to keep near my ear, its like a dead piece4) When i try to uninstall the drive , it gets uninstall with messsage that IOMEGA ego drive, its safe to uninstall.I want to know what is the possible solution of this problem