In this post, you’ll learn more about the Oracle ErrorORA-12519: TNS:no appropriate service handler found with the details on why you receive this error and the possible solution to fix it.
Oracle Error Description
ORA-12519: TNS:no appropriate service handler found
Reason for the Error ORA-12519: TNS:no appropriate service handler found
The listener could not find any available service handlers that are appropriate for the client connection.
How to fix the Error ORA-12519: TNS:no appropriate service handler found ?
You can fix this error in Oracle by following the below steps
Run “lsnrctl services” to ensure that the instance(s) have registered with the listener, and are accepting connections.