Back it up ASAP, The disk is on it's way out. I'd be weary about using it before baking up, there really isn't much in terms of warning for when a disk is going to stop spinning for you and one it's gone it's gone. Whats wrong with your drive is probably just that.
When you unplug the disk does it reset the disks MBR?, if so that could be why it boots up fine after unplugging/replugging. once windows turns on and tells the MBR there's a problem it won't let you boot.
keep us updated.
When you unplug the disk does it reset the disks MBR?, if so that could be why it boots up fine after unplugging/replugging. once windows turns on and tells the MBR there's a problem it won't let you boot.
keep us updated.