I have rather a strange occurence. I have had a Toshiba USB 3.5" hard drive for Christmas. I thought I would only need to plug it in and away I go. It doesn't seem that simple. I need to go into Control panel>system>device manager>hard drives, then properties to see the hard drive in my computer. I have given it a drive letter, but it still doesn't show in the drives attached. What, if anything am I doing wrong?