Well, you've provided absolutely NO information - computer model, operating system, software being used, or what you were trying to do when you encountered this error. So, as my crystal ball is in the shop for repairs today, I have no idea.

That sounds like a 32-bit diagnostics HD test, or a SMART or 90-90 test.  In any case, it was a hard drive test, and it failed.  Could be an indication that the drive is starting to go.  

If the drive is still bootable, I would definitely take the opportunity to back up any important data to an external hard drive, USB thumb drive, or even burn to CD/DVD, as there's just no telling how long the drive will continue to remain functional.  Could work for another year, could work for another hour.  Could already be pooched.

If the system is still under warranty, you may be able to call Dell, provide the service technician with that number and message, and with possibly some additional light troubleshooting, have the drive replaced.