FreeBSD harddisk error - read (06) medium error info unrecovered pls help...

[Jessica Kung]

Dear netizens

Help! I am running FreeBSD and encountered the following error in 
booting up.

(da0:sym 0:0:0) read (06) CDB: 8 0 0 bf 10 0
(da0:sym 0:0:0) Medium error info: c8 csi: 0, 0, 0, c8 asci: 11, c
(da0:sym 0:0:0) Unrecovered read error - recommend rewrite the data 
field replacable unit: 6 b sks: 80, 74

Any help is much appreciated!

Thanks in advanced!

Jessica