Booting error

Hi everyone

I have purchased a BB rev B5, and am trying to boot it.
Here is the error I am getting from my HyperTerminal.

Texas Instruments X-Loader 1.4.2 (Feb 19 2009 - 12:01:24)
Reading boot sector
Error: reading boot sector
Loading u-boot.bin from nand
Skipped bad block at 0xc0000

I can't type anything into the terminal.

Any suggestion?