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Ora-12518 on Oracle 12c Multitenant Architecture (Doc ID 2252001.1)

Last updated on MARCH 31, 2022

Applies to:

Oracle Net Services - Version and later
Oracle Database - Enterprise Edition - Version to [Release 11.2]
Information in this document applies to any platform.


When attempting to connect to PDB via listener,
the following error occurs.


ORA-12518: TNS:listener could not hand off client connection

Listener log:


03-APR-2017 08:57:31 * (CONNECT_DATA=(SID=wd1)(CID=(PROGRAM=d:\orasfw\prd1\bin\sqlplus.exe)(HOST=Host name )(USER=ismeirb))) * (ADDRESS=(PROTOCOL=tcp)(HOST=XX.XX.XX.XX)(PORT=63994)) * establish * wd1 * 12518

TNS-12518: TNS:listener could not hand off client connection
TNS-12560: TNS:protocol adapter error
TNS-00530: Protocol adapter error
64-bit Windows Error: 203: Unknown error


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