ORA-12638: credential retrieval failed - Solved

Oracle Forms unable to connect to the database and returns the error  ORA-12638: credential retrieval failed.

Not much to explain, you can get rid of this error by modifying the sqlnet.ora file.

Solution : 

1. Find sqlnet.ora file in your forms installation
   It will be in $ORACLE_HOME/Network/Admin folder.
   My location is as below.
   C:\Oracle\Middleware\Oracle_FRHome1\network\admin
2. Find the line SQLNET.AUTHENTICATION_SERVICES= (NTS)
3. Change it to SQLNET.AUTHENTICATION_SERVICES= (NONE)

Screenshots are actually not needed for this simple modification, but still don't want to change the blog pattern. look at the screenshots if you still need it.

Solution : 

Current Sqlnet.ora file.

Modified file.

Contact us over comments if you face any such errors.