It appears you are trying to boot to that hard drive.
Is/was this hard drive the primary drive in your computer?
Yes to both.
You need to provide more details in order for us to understand the original problem.
Sorry, I was just trying to keep it concise with what I figured was the crux of the matter. These are the entire details...
I was working on my computer (replying to an email as I recall, not likely relevant) and suddenly there was 100% drive access for a few minutes, everything froze and then windows starting throwing several random and obscure errors.
explorer.exe and many other running programs crashed (just closed or errored out), CTRL+ALT+DEL didn't work, my only choice was a hard power-off (hold power button until the machine is physically off)
Booted up, which obviously triggered a safe mode prompt. Safe mode got stuck loading one of the drivers, had to hard power-off.
Tried restoring a backup of image of the system/OS partition, which failed almost immediately.
This is my HDD setup: [TC/WIN7] [UBUNTU] [[LINUX SWAP] [DATA AND BACKUPS]]
At this point, I don't care about either operating system, I just want to be able to access my data.
When I boot, it sometimes fails completely with "2100:Detection Error on HDD0 (Main HDD)". If it makes it past that error, it attempts to load a TrueCrypt'd Windows 7 installation by default, which always gives "No bootable partition found". Ubuntu (unencrypted, GRUB in /dev/sda2 and not MBR) does boot in this scenario, I can load the OS, login and access the desktop. But within a minute or two, it just jams out the same way Windows did (100% HDD access, completely hangs, errors, etc.)
Boot into Ubuntu, mount [DATA AND BACKUPS] partition
Connect HDD externally to another PC using USB SATA adapter in Windows or Ubuntu:. It either fails to mount entirely or mounts and dismounts itself after a few seconds. I'm never able to get as far as listing files.
My imaging software (TBU IFL) is the only software I've found that is able to access the drive, see the partitions and list files on the partitions. I tried imaging the [DATA AND BACKUPS] partition which failed at about 3% completion with the error that it can't access the data.
Every related utility in UBCD (mostly Parted Magic and it's contained utilities) is unable to mount or read the drive. Sometimes GParted can list partitions but, again, it dismounts after a minute or two.
Do you have a Lenovo Thinkpad?
Yes, Lenovo W520, hard drive is Seagate ST9750420AS (750GB, 7200 RPM). SeaTools can't see the drive, I've made multiple attempts.
The drive is sensing an internal failure and is either shutting down or spinning down. You can make a JTAG cable for your drive and find the telnet commands for your drive's firmware, but it is some tricky stuff. It requires you to have a high aptitude with electronics. Most computer repair shops would not be able to do this job.
I've installed dd-wrt on a few routers and I work in the Linux shell almost daily, so I'm vaguely familiar with what you're talking about there.
If the data is really important you could always send the drive off to a data recovery company.
Yeah, I'm considering it at this point. I'll wait for some responses after this post.