ORA-12638: Credential retrieval failed

Question

I have a legacy VB6 application which I've inherited. The issue I'm facing is that I'm getting the infamous

ORA-12638: Credential retrieval failed 

error message whenever it tries to connect to one of our Oracle databases. I can connect fine from SQLPlus and Toad, however. I've Googled around and everyone seems to say that modifying their sqlnet.ora file to

SQLNET.AUTHENTICATION_SERVICES=(NONE) 

did the trick. I have yet to find anyone with an alternative fix. Here is what my connection string looks like:

"PROVIDER=OraOLEDB.Oracle;DATA SOURCE=(DESCRIPTION = " & _ "(ADDRESS = (PROTOCOL = TCP)(HOST = server1) (PORT = 1521))" & _ "(ADDRESS = (PROTOCOL = TCP)(HOST = server2) (PORT = 1521))" & _ "(LOAD_BALANCE = yes) " & _ "(CONNECT_DATA = " & _ "(SERVER = DEDICATED) " & _ "(SERVICE_NAME = database_name_here) " & _ ") " & _ "); " & _ "User Id=username_here;Password=password_here;" 

As for my VB code, it's quite simple.

Private oracleDatabaseConnection As ADODB.Connection  Set oracleDatabaseConnection = New ADODB.Connection oracleDatabaseConnection.Open oracleConnectionString 

Anyone have any ideas?

Thank you. :)

Answer 1

I know this is a very old post but I have found a solution that has worked for me (Legacy VB6 Application):

Change the following entry in the sqlnet.ora file:

Original Entry - SQLNET.AUTHENTICATION_SERVICES= (NTS)  Modified Entry - SQLNET.AUTHENTICATION_SERVICES= (NONE) 

Here is a LINK to the solution