For customers experiencing this issue, refer to the entry below from Symantec's In Defense of Data blog:
We don’t often post about product compatibility problems on In Defense of Data blog, but we want to make sure customers are able to access this important information.
Symantec is aware of an issue with Mac OS X 10.6.5 and PGP Whole Disk Encryption 10.0.x. At this time, we recommend that customers using PGP Whole Disk Encryption do not upgrade to Mac OS X 10.6.5.
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