When attempting to perform PGP Whole Disk Encryption (PGP WDE) on the boot disk of a Mac, you receive the following error message:
An Error occurred while encrypting your disk: PGPError #18
This issue is caused by a missing system file in the folder /Library/Preferences/SystemConfiguration on the system. The name of the file is com.apple.Boot.plist.
PGP WDE requires this system file on a Mac with an encrypted boot disk, but is not required on systems booting without PGP WDE.
Note: This article applies to PGP Desktop 9.9 and above running on Mac OS X 10.4 and 10.5 systems. Encryption of the boot drive is available on Intel enabled Mac OS X 10.4 and 10.5 systems.
This issue can be resolved by creating the missing system file (com.apple.Boot.plist) using a plain text editor or the Property List Editor. The Property List Editor is only installed with the Apple Developer tools. The file must be created in the /Library/Preferences/SystemConfiguration folder. The folder is protected and requires administrative privileges to create the file in the folder.