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ORA-12500 When Connecting Via the Listener to an Instance in a Separate ORACLE_HOME (Doc ID 299130.1)

Last updated on FEBRUARY 03, 2019

Applies to:

Oracle Net Services - Version: 8.1 to 9.2
This problem can occur on any platform.


New connections to a listener, running on a UNIX operating system, from one Oracle version to a database from another Oracle version on the same machine may result in an ORA-12500.

ORA 12500 "TNS:listener failed to start a dedicated"

This error will occur for all remote connections to the database in the foreign home.  It is not intermittent.   If the same listener is used to connected to a database in the same $ORACLE_HOME, the connections are successful.


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In this Document

Checked for relevance on 07-FEB-2008.

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