I'm having quite a problem here. My external hard drive (Astone - 2Tb) isn't showing up on my computer - or anybody else's. I lent it to a friend, and I believe he may have been rough with it (The base is missing 2 screws), and after receiving it back the following day, I plugged it into my laptop. It came up with "Installing device driver software" which is odd, since I've used it on there many times before. Afterward, it would flash in My Computer for a second coloured grey, then disappear. It does not appear in Safety Removal Hardware either. I've tried this on several computers, but with no difference, and the blue light still works. The problem is definitely with the Hard Drive, since thumbdrives still work fine. Reformatting isn't an option, because there are important, irreplaceable files on there. It does, however, show up in control panel > Hardware and Sound > Devices and Printers. I still can't access it though - When I right-click and go to browse files "Removable Disk (D " is written in grey. In computer management, it is simply called Removable Disk and cllaims to have no media. Is there anything you tech geniuses can do to help? I'm really getting desperate here...
You can try a Linux LiveCD and see if you have better luck. You can also try to open the enclosure and see if the drive inside is actually the good one (some friends aren't really friends) and try to plug it directly into your machine as regular drive.
If none of that works, you might be "attached to another object by an incline plane wrapped helically around an axis".
so you lent your HDD which was working fine (and containing irreplaceable files on it) to a friend. when you get it back it no longer works, has to reinstall drivers (clue #1), and has 2 screws missing (clue #2).
Sounds to me like the problem is your 'friend' swapped a dead HDD for your working one, that would account for reinstalling drivers, missing screws, lack of media...
better be sure before you go accusing your friend of anything. do you know what make/model 2TB HDD you originally had in it? can you verify it still is?
Inside the enclosure will be a USB-SATA bridge board. If the bridge chip detects a hard drive, then it enumerates the enclosure as a "USB mass storage device". Your OS will already have installed the drivers for such a device. In fact your thumb drive uses the same driver.
However, if the hard drive is not working, then the bridge IC may identify itself using its own Product ID and Vendor ID. For example, some Seagate and WD external products may identify themselves as a "Default Initio Controller". In such case the OS will ask you for a driver.