Since the new XenMobile PKI integration capabilities have been significantly enhanced, migrating to the new system is not automatic. If you had used PKI configurations in previous versions, you will be able to continue to use these in 8.0 without changes, but if you wish to make use of the new capabilities, you will have to manually upgrade existing PKI entities.
Your pre-8.0.1 PKI entities (Microsoft CA or GPKI) will appear in the list of PKI entities, but will be marked as not ready to be used, indicated by a red icon in the Valid column in the Options dialog box, under PKI > Entities.
To ready the entity for 8..10 usage, edit the entity and provide the missing settings (the system will indicate which settings are missing when you try to save the configuration). This process requires providing the CA certificate(s) for the entity.