I also found this solution:
Step-by-step
This step-by-step details the procedures for creating and using a recovery USB drive for Microsoft Windows 8 UEFI-based systems encrypted with Symantec Drive Encryption.
To create a recovery USB drive
Caution: Ensure the drive is a USB 2.0 drive, with a minimum of 1 GB of space.
1.Format a USB drive using the FAT32 format.
2.In the root directory on the drive, create a folder named EFI.
3.In the EFI directory, create a subfolder named Boot.
4.Copy the following files from the C:\Program Files (x86)\PGP Corporation\PGP Desktop directory, to the newly created \EFI\Boot folder on the USB drive:
bootx64.efi
pgpcontents.tar
The USB drive is now a bootable UEFI drive.
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To use a recovery USB drive
1.Insert the drive into your system.
2.Access your system's boot option menu (usually by pressing F9, F10, or F12 immediately after powering up Windows, but consult the user guide of your PC for more detail).
3.Select the USB drive (or, on some systems, select the \EFI\Boot\bootx64.efi file on the USB drive) from the boot option menu to boot the recovery USB drive.
The PGP BootGuard authentication screen displays as usual. If the encryption record is still intact, you have the option either to boot directly into Windows or to decrypt without booting, after a successful authentication. If the drive encryption record has been damaged, the recovery drive scans the hard drive and attempts to recover the record. If the recovery is successful, you have the option to decrypt the hard drive after authentication
But this doesn't work, because i use Win7.