Installed a second hard drive, computer works as normal, however, it doesn't show up in My Computer and I can't open it, for example, to save a file in.
It only shows up when i go into "Device Manager" under "Disk Drives"
is it a new drive? if yes you need to format it, if not, then you need to a give to it a letter:
administrative tools, computer management, disk management and the option of your drive "change drive letter"