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Every Second Connection Fails with TNS-12638 When Using NTS and Active Directory (Doc ID 577844.1)

Last updated on JUNE 16, 2022

Applies to:

Oracle Net Services - Version to [Release 10.2 to 11.2]
Oracle Net Services - Version to [Release 10.2 to 11.1]
Microsoft Windows Itanium (64-bit)
Microsoft Windows x64 (64-bit) Microsoft Windows Server 2003 (64-bit Itanium)Microsoft Windows Server 2003Microsoft Windows Server 2003 (64-bit AMD64 and Intel EM64T)


When you connect to the database, the first connection succeeds, but the second connection (from the same sqlplus session) fails with TNS-12638 "Credential retrieval failed".

Both clients and server have SQLNET.AUTHENTICATION_SERVICES set to NTS. Users are authenticated via Active Directory (AD).


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