ORA-12154: TNS:could not resolve service name

Today, we made a SFC program, the strange is: when the code try to connect Oracle using TNS connection string, always pop up an error: "ORA-12154: TNS:could not resolve service name". Toad can use the same TNS connect Oracle on the same machine. After 2 hours trying, I found the project folder name has "(XXXX)", after I remove the "()" of ther folder, everything is OK!

P.S. There is another connection error when I 1st use Toad connect DB. because the sqlnect.ora file has one line: SQLNET.AUTHENTICATION_SERVICES= (NTS), after I modified: SQLNET.AUTHENTICATION_SERVICES= (NONE) is OK