This is in reference to "balck screen just saying: bootguard" at link: https://www-secure.symantec.com/connect/forums/balck-screen-just-saying-bootguard
The faster fix is to boot to the PGP Bootguard Recovery Boot Disk for your particular version (mine is 10.0.0) have the person enter the passphrase at the PGP Menu for accessing the encrypted drive.
DO NOT PRESS "D" to Decrypt the drive, but press use the "Press any other key to continue" option.
Logon to your Windows account (mine is Windows 7 Pro).
Perform a Repair of the installed PGP Software via Control Panel/Programs and Features (maybe 5 minutes).
Remove the Recovery Disk and a reboot of the system fixes the problem.
This sure beats spending hours to Decrypt and re-Encrypt the drive.
-Glen