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Ora-12638 When Connecting Or Reconnecting On Windows XP Or Windows 2003 (Doc ID 437895.1)

Last updated on FEBRUARY 01, 2022

Applies to:

Oracle Database - Enterprise Edition - Version and later
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
z*OBSOLETE: Microsoft Windows XP
z*OBSOLETE: Microsoft Windows Server 2003


During a connection to the database using operating system authentication, ORA-12638 "Credential retrieval failed" is logged intermittently. In some rare cases the problem is only seen when reconnecting. This can happen using any OCI based tool, like Sql*Plus.

As soon as clients are rebooted it works fine for a few days.

The database server is running on Windows 2003.
The Oracle client uses NTS authentication in sqlnet.ora.


In a sql*net server trace file (trace_level_server = 16) the following is reported:

[24-MAI-2007 14:24:29:638] naun5authent: Authentication type is 0 
[24-MAI-2007 14:24:29:638] naun5authent: SSPI: 0x8009030e error in InitializeSecurityContext 
[24-MAI-2007 14:24:29:638] naun5authent: exit 
[24-MAI-2007 14:24:29:638] naunauthent: exit 
[24-MAI-2007 14:24:29:638] nau_ccn: get credentials function failed 
[24-MAI-2007 14:24:29:638] nau_ccn: failed with error 12638 


Comment: the textual equivalent to 0x8009030e is SEC_E_NO_CREDENTIALS .


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