ORA-12638: Credential retrieval failed

Hello Everyone,

I recently installed Oracle 9i Database release 2 (enterprise/standard/personal edition) on a Windowx XP machine. I installed the standard, general purpose edition and am having some problems getting it to work. Specifically, when I try to connect to the database (test connection) or log into SQL plus I get the following error message:

ERROR:
ORA-12638: Credential retrieval failed

I am using the scott/tiger username/password to make this connection. I noticed that many people have previously suggested to:

#1) Modify the line SQLNET.AUTHENTICATION_SERVICES= (NTS) in sqlnet.ora file
to be SQLNET.AUTHENTICATION_SERVICES=(NONE). Some have suggested commenting it out.

Or

#2) Modify the line SQLNET.AUTHENTICATION_SERVICES= (NTS) in sqlnet.ora file
to be SQLNET.AUTHENTICATION_SERVICES= (BEQ,NONE).

This has not worked for me since when I make the changes I get another error message:

ERROR:
ORA-03113: end-of-file on communication channel

I am relatively new to Oracle and am struggling to figure out what to do. If anyone could provide any help. I would be very grateful.

Thanks in advance for your time and effort.

• Saurabh.