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Windows: Connections Fail with ORA-12640 or ORA-21561 (Doc ID 744125.1)

Last updated on DECEMBER 17, 2018

Applies to:

Oracle Net Services - Version to [Release 10.2 to 12.2]
Oracle Database - Enterprise Edition - Version to [Release 11.2 to 12.2]
Generic Windows


Connections to database fail, reporting the error code ORA-12640 Authentication adapter initialization failed. SQLNET.AUTHENTICATION_SERVICES is set to NTS in the SQLNET.ORA file. Changing SQLNET.AUTHENTICATION_SERVICES=NONE and connections then fail with the error code ORA-21561 OID generation failed.

Seen for connections using third party applications and oracle tools such as recovery manager (RMAN).

A typical Oracle Net level 16 client trace of RMAN failure shows following:

[21-JAN-2010 10:14:55:097] nsc2addr: (DESCRIPTION=(ADDRESS=(PROTOCOL=BEQ)(PROGRAM=oracle)(ARGV0=oracleBOXIDB)(ARGS='(DESCRIPTION=(LOCAL=YES)(ADDRESS=(PROTOCOL=beq)))'))(CONNECT_DATA=(SID=ORCL)(CID=(PROGRAM=C:\oracle\ora102\bin\rman.exe)(

o Connect packet :

[21-JAN-2010 10:14:55:097] nscon: sending NSPTCN packet

o Accept packet :

[21-JAN-2010 10:14:55:097] nscon: got NSPTAC packet

o shortly after the accept packet and client authentication :

[21-JAN-2010 10:14:55:129] nau_gse: failed with error 12640
[21-JAN-2010 10:14:55:129] nau_gse: exit
[21-JAN-2010 10:14:55:129] nau_cga: failed with error 12640
[21-JAN-2010 10:14:55:129] nau_cga: exit
[21-JAN-2010 10:14:55:129] nau_ccn: failed with error 12640
[21-JAN-2010 10:14:55:129] nacomsd: entry
[21-JAN-2010 10:14:55:129] nacomfsd: entry
[21-JAN-2010 10:14:55:129] nacomfsd: exit
[21-JAN-2010 10:14:55:129] nacomsd: exit
[21-JAN-2010 10:14:55:129] nau_ccn: exit
[21-JAN-2010 10:14:55:129] na_csrd: failed with error 12640
[21-JAN-2010 10:14:55:129] na_csrd: exit
[21-JAN-2010 10:14:55:129] nacomer: error 12640 received from authentication service


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