After a package that includes Full Disk Encryption is successfully installed on a client, many requirements must be met before the Full Disk Encryption policy can be enforced. Before these requirements are met, the Pre-boot does not open. The period of time between the installation and when the policy can be enforced is called the Full Disk Encryption Deployment Phase.
To move from Deployment phase to Full Disk Encryption policy enforcement, these requirements must be met:
If there is communication between the client and server and the client meets the Client requirements, all of the requirements are completed automatically. However, if these requirements are not met, Full Disk Encryption cannot protect the computer and the Pre-boot cannot open.