A- This message associated mainly with the hard disk , either the disk has a mulfaunction and needs maintenance Via software maintenance Or hardware and pray not to the last in the first case just try fromat the whole disk and repartioning it by partion magic boot cd.
B-
In case you die for the data on that disk all you need is a (7-zip filemanager) like software - its found @ any bootable maintenance cd - then had a another media to retrieve date to
Other common software for such plan-B
1- ERD Commander 2003 Explorer
2- Explorer2fs (Not recommended-little complicated)
3- Opera web browser in case you lost data on server so you can downlad it to another (media i.e another hard)
Note - to make sure it's not a hardware mulfuntion put your hard disk on another board and seek bios setting, watch if the board identify the HDD
Most of brevious softwares mentioned above and more located on Cd labled Hiren's BootCD verion 10.2
(in case you don't get any of what i've said, you should go to a maintenance centre) tell your story...
Finally, i hope i have helped