external HD problem

hi all

bought myself an imac plugged in my old ex hd drive, seemed ok, copied some music into itunes, so far so good.....

then when transfer had completed i turned off the ex hd, i think i had a message on the mac saying i should 'quit' properly the ex hd before turning it off ......... since then the ex hd is unreadable ........ is this terminal or can i do something to get it back ........ it's a copy of my old pc .... lots of valuable info

thanks in advance for any advice

ex hd = seagate 500gb

Before unplugging (or powering off) any external drive on a Mac, you should always "eject" it first. This is actually recommended in Windows too. More likely than not, that drive was formatted using FAT32 and you probably have a corrupt directory as a result of the forced dismount. Turn it back on and leave it on for a bit. OS X may rebuild it on its own given enough time. You may have to reboot after powering it on and leave it be.

If the files never re-appear, don't give up hope. The files aren't lost… it's just that the OS doesn't know where on the drive they physically lay. You can try to recover them using Disk Utility with the verify/repair Disk options. If that doesn't work, you may need a dedicated 3rd party tool.