After not being able to auto-install Win 7 (64-bit) updates for months (>6 months), and observing that MS engineer tech support did not help matters, I finally resorted to decrytping the HDD (PGP-WDE 10.1.2) and observed that 17 updates were available -- all of which installed successfully. Prior to this point, there were 2 updates which always (constantly) failed.
Suggestion is for PGP to contact MS to debug why PGP-WDE 10.1.2 on Win 7 (64) does not allow updates to reach all areas on disk needed for updates. For example, other than the MBR, there has to be hive files (and/or others) in regions of the HDD which are cloaked by PGP-WDE that prevent WIn updates from successfully occurring -- because as soon as I decrypted the HDD, the updates were successfully installable.
Not being to update Win 7 places PGP-WDE users at increased security risk -- so it is in both parties interest to debug this in future versions of PGP-WDE.