Harddisk Failure

I have an external IDE Seagate hardisk.
I accidently turned the power off of the external hardisk before I close my windows XP.

When I reboot, I got the message that the files on external hardisk is corrupted and cannot be accessed.

I can see my external drive but when I click on it – it says the file is corrupted and cannot be accessed. The hard disk was formatted with NTFS system.

What shall I do?

Thanks.