ORA-12660: Encryption or crypto-checksumming parameters incompatible
Cause: One side of the connection specified “REQUIRED” for encryption or crypto-checksumming, while the other side specified “REJECTED”.
Action: Change the “REQUIRED” side to “REQUESTED” if the you want encryption or crypto-checksumming to be optional, or change the “REJECTED” side to “ACCEPTED” if you do not want the service to be optional.