I have an OWC Mercury on-the-go 160GB hard drive that was used on a Mac and I have plugged it into my PC (running Windows 7). It does not appear under "My Computer" though I can find it in Disk Management labeled as Disk 1 and also under Devices and Printers. I can't figure out how to have it recognized as a drive letter so that I can use it as a Back-up device. When I right click on "Disk 1" under disk management, the choice for reassigning is grayed out. Was thinking of reformatting, but have no drive letter to do so in command prompt. Can someone please help?