We're getting ready to upgrade to DE 7.1.1, have the same GPO enforcement and OPAL drives. So I am curious to know the answer to this also. Thanks.
I have found the cause and fix.
Its the Product settings for the Drive Encryption policy... Look for the "Log On" tab then look at "Enable SSO." Toggling this off will bring back the Ctrl Alt Del prompt. We are using Reactive Autoboot, so it's less important for us-- For PBA users, i guess it's just a matter of knowing and expecting this will happen. Might as well discard the GPO because it will be useless after enabling SSO.
What annoyed me was I had been on a month long quest to figure this out and tier 1 and 2 support seemed baffled by it-- and had me chasing non problematic group policies and installing patches and drivers one by one on OEM images. Seems like a pretty straight forward config to understand.@