When a drive is partially or fully encrypted with PGP Desktop using Whole Disk Encryption and a signle sign-on user, Cisco Security Agent will cause the system to hang at the logon screen.
This issue is caused by Cisco Security Agent.
This is a known compatibility issue. Since Cisco has issued an end-of-life statement for Cisco Security Agent, no fix is planned for PGP Desktop. We recommend considering a compatible endpoint security product such as Symantec Endpoint Protection (SEP).
Windows XP*, Cisco Security Agent, PGP Desktop with Whole Disk Encryption in use with single sign-on
* This has been confirmed in a Windows XP environment. It may affect other versions of Windows.