With this release, Cisco Prime License Manager supports the encryption license, which enables the higher levels of the product encryption for the registered products. Some newer Cisco products, such as Cisco Unified Communications Manager, Release 10.5(2)SU6 and Cisco Unity Connection, Release 10.5(2)SU6 require an encryption license to run the product in mixed mode.
Procure the encryption license along with the PAK and install it. For more details on buying the licenses, see the Ordering Guide at http://www.cisco.com/c/en/us/partners/tools/collaboration-ordering-guides.html.
For more details on encryption fulfillment, see "Configuration" chapter of the Cisco Prime License Manager User Guide at http://www.cisco.com/c/en/us/support/cloud-systems-management/prime-license-manager/products-user-guide-list.html.