I am trying to register oracle 12cR2 geo-database Server through ArcGIS Server 10.8. as database authentication. But error generate "The connection property set was missing a required property or the property value was unrecognized. Unspecified error. i have installed 64bit oracle client on Arc Server machine and configured it correctly and verified through Listener / service and SQL Plus connection. Database server is connected through Arc Map and working efficiently. In environmental variable the 64bit client is place first and 32bit client place 2nd. Anyone have idea to resolve this problem?