we use guardian edge software encryption at my company and every time there is an issue the drive has to be decrypted first before we can work on it. its a pain in the arse. If you boot the system up using BartPE or Hirams boot disk, you wouldnt be able to access the drive since the encryption is still in place.
what kills me is that though i understand it its a pain to work with, but when a system has a MBR error, you cannot use windows repair cmds to fix the MBR since the windows MBR is backed up and replaced by a Guardian Edge MBR. I spend alot of time decrypting just to fix the MBR, which is funny casue when the decrypt is done, it has replaced its MBR with the original windows and the machine will then boot. like i said.. its a pain