DeviceLock Management Console becomes unresponsive when connecting to DeviceLock agent and trying to view USB Devices White List which contains more than 40,000 unique devices, or when trying to load a service settings file (.DLS) with the same number of unique entries.
This problem is related to the peculiarity of the RPC protocol realization which has a limitation for the buffer and happens due to RPC buffer size overflow.
1) Use Group Policy to deploy DeviceLock settings with USB Devices White List which consists of more than 40,000 unique entries.
2) It's not recommended to have 40,000 unique devices in a single settings file. You can, for instance, separate all your clients into 2 groups and apply settings with ~20,000 USB Devices White List entries on each independently.