i would like to know how i can get my external hard drive to open up in mycomputer for some reason there is no hard drive icon if anyone has a fix to this please let me know.
If it is new then it is not formatted to be recognized by Windows. It should have come with a disc of some kind. That disc will allow you to format it to NTFS or FAT32 to be recognized by Windows and be used.
Well then you will have to try GParted LiveCD or a Linux LiveCD. Since Windows doesnt recognize RAW format and you say that disk management doesnt see the drive there isnt much you can do.