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ORA-28547: connection to server failed, probable Oracle Net admin error
Cause: A failure occurred during initialization of a network connection from a client process to the Oracle server: The connection was completed but a disconnect occurred while trying to perform protocol-specific initialization, usually due to use of different network protocols by opposite sides of the connection. This usually is caused by incorrect Oracle Net administrative setup for database links or external procedure calls. The most frequent specific causes are: -- The connection uses a connect string which refers to a Heterogeneous Services agent instead of an Oracle server. -- The connection uses a connect string which includes an (HS=) specification.
Action: Check Oracle Net administration in the following ways: -- When using TNSNAMES.ORA or an Oracle Names server, make sure that the client connection to the ORACLE server uses the correct service name or SID. -- Check LISTENER.ORA on the connection end point's host machine to assure that this service name or SID refers to the correct server. -- Confirm in TNSNAMES.ORA or the equivalent service definition that the connect string does NOT contain (HS=).

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