i must connect to a sql server with windows authentication

sql server is on machine 192.168.3.6 web server (client) is on my machine 192.168.3.10

I'm using JTDS driver

dbUrl=jdbc:jtds:sqlserver://192.168.3.6:1099/db_test;instance=test
Connection con = DriverManager.getConnection( dbUrl, "", "" );

I have username and password of administrator user of sql server !

I also put ntlmauth.dll into c:\windows and c:\windows\system32 and I have always error:

java.sql.SQLException: Login failed for user '(null)'. Reason: Not associated with a trusted SQL Server connection.

Any idea to solve my problem ? Thank you very much

sql-server jdbc
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