Ubuntu 'drdy' ERROR

When hard drive is connected Ubuntu won't boot. If get an error screen which reads:

[272.854943] ata2.00: status: {DRDY err}
[xxx.xxxxxx] ata2.00: error: {UNC}
[xxx.xxxxxx]ata2.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
[xxx.xxxxxx] ata2.00: BMDMA stat 0x24
[xxx.xxxxxx] ata2.00: cmd c8/00:08:00:00:00/00:00:00:00:00/e0 tag 0 dma 4096 in

the x's are all different numbers. The message repeats several times. Sometimes it says Buffer I/O error on device sdb1, logical block x (where x is a changing number)
The drdy error means "Disc Ready error".
Try burn the live cd, SystemRescueCD although any live cd with the right tools should work.

Then run:
e2fsck -f -c -v /dev/sda1

substituting /dev/sda1 with your device with the error.

This will force a check of the drive even if fsck believes the drive is ok.