I have this Seagate Expansion Portable Drive 320GB at work. It was working fine until my co-worker unplugged its USB from the computer without safely removing it. When I plugged it back in the computer, the computer cannot detect it anymore. If it did, it would just show "Local Disk (F)" as opposed to "Seagate (F)" before. When I try to double-click on the drive, it would say that the drive is not formatted.
The files in the drive is important as this is the archive of what our department has done for the past years. How can I repair the drive without formatting? If the drive is not repairable without formatting it, how can I recover the files before reformatting?
The drive was probably still finishing writing a file and the MBR was corrupted by the disconnection.
There are a number of things that could work.
If it shows up in disk management you can often just assign it a drive letter.
If it shows up in disk management and you can't just give it a drive letter, open the command prompt box
type in chkdsk #: /R (where your problem drive letter is #)
let chkdsk repair the damage
Another that sometimes works is Go to My Computer, right click Properties
select the Hardware tab, select Device Manager, find your external hard drive (USB mass storage device), if it has a red X, then click the drive and select to enable it. Sometimes it seems that you may need to uninstall the drive and then restart and that will repair it.
In this situation, you have to format your Seagate hard drive in order to use it further. But you may lose your data when the hard drive is formatted. Don't worry you can recover data from formatted hard drive with the help of Hard Drive Recovery software. When I faced the similar situation I was able to restore Seagate SATA hard drive data by using this third party tool.