Disk ID all 0's

I have a laptop at a remote site with pre-boot logon issues. The Admin passphrase does not work. Usually when this happens(which is way too often) we can WDRT to get in.  I provide the WDRT and it fails with "incorrect authentication. Please try again". One thing the user is telling me is the Disk ID shown on the WDRT screen is all 0's. Any ideas around this? We tried the recovery disk with the same result. Thank you.