When attempting to encrypt a disk using the pgpwde --secure command you encounter the following error:
Error code -11990: read failed
This is usually caused by some instrumentation being left behind in the Master Boot Record (MBR) from a previous encryption performed on the disk. This can happen when encrypting your disk and then removing the partition tables, reformatting and reinstalling the Linux operating system over the top of the encrypted disk or re imaging the disk. You can tell if you are affected by this problem by running a command to check the status of encryption on the disk:
pgpwde --status --disk 0 (replace disk 0 with the correct disk number if this is not the primary drive that you are working with)
Check if the output of this command states that the drive is instrumented but the instrumentation data is invalid.
Symantec Drive Encryption (formerly PGP Whole Disk Encryption)
Linux 2.6 kernel or newer