RSA1 Database error 12154 at CON issue

Good day,

I am trying to extract data from an Oracle database that is hosted on

another server.

I have configured the tnsnames.ora at the OS level.

I completed a test with tnsping and also connect to the database via

sqlplus. Everything works fine at the OS level.

I have created the connection parameters via tx:DBCO

However i get the system message with text "Database error 12154 at CON"when i create a DB connection via tx:RSA1.

Regards,

Tolu