For the system transfer and user assignment to be successful:
the destination server should have all relevant AD servers configured as registered servers.
if chase referrals is enabled, ensure that all AD servers are reachable.
the system transfer feature should be enabled on the destination server, using the web-API.
an appropriate AD search order must be specified if the destination server has more than one LDAP server using the web-API.
the maximum number of users that can be transferred may be specified through the web-API - if no limit is specified, a default limit is used.
branch users should be pre-assigned within the destination server.
Drive Encryption system policy should be appropriately configured in the destination server.
Drive Encryption user-based policy should be appropriately configured in the destination server.
appropriate Drive Encryption theme and simple words configuration should be made in the destination server.
suitable policy-assignment rules should be configured (if applicable).
any systems that inherit user/group assignments by system tree location should be pre-populated in the destination server, in the correct system tree location.