无法使用sqljdbc4.jar连接到MSSQL Server 2012

我无法使用sqljdbc4.jar从我的Java应用程序连接到MSSQL Server 2012 .

以下是我的代码：

public static void main(String[] args) {
    String connectionUrl = "jdbc:sqlserver://172.16.0.4:1433;" +
             "databaseName=PUC;user=admin;password=admin;instanceName=mssqlserver2012";

    // Declare the JDBC objects.
    Connection con = null;
    Statement stmt = null;
    ResultSet rs = null;

    try {
        // Establish the connection.
        Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
        con = DriverManager.getConnection(connectionUrl);

        // Create and execute an SQL statement that returns some data.
        String SQL = "SELECT TOP 10 * FROM Patron";
        stmt = con.createStatement();
        rs = stmt.executeQuery(SQL);

        // Iterate through the data in the result set and display it.
        while (rs.next()) {
            System.out.println(rs.getString(4) + " " + rs.getString(6));
        }
    }

    // Handle any errors that may have occurred.
    catch (Exception e) {
        e.printStackTrace();
    }
    finally {
        if (rs != null) try { rs.close(); } catch(Exception e) {}
        if (stmt != null) try { stmt.close(); } catch(Exception e) {}
        if (con != null) try { con.close(); } catch(Exception e) {}
    }
}

以下是错误：

com.microsoft.sqlserver.jdbc.SQLServerException: Login failed for user 'admin'. ClientConnectionId:1530f396-0935-4c41-92f1-016797a65edd
    at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDatabaseError(SQLServerException.java:216)
    at com.microsoft.sqlserver.jdbc.TDSTokenHandler.onEOF(tdsparser.java:254)
    at com.microsoft.sqlserver.jdbc.TDSParser.parse(tdsparser.java:84)
    at com.microsoft.sqlserver.jdbc.SQLServerConnection.sendLogon(SQLServerConnection.java:2908)
    at com.microsoft.sqlserver.jdbc.SQLServerConnection.logon(SQLServerConnection.java:2234)
    at com.microsoft.sqlserver.jdbc.SQLServerConnection.access$000(SQLServerConnection.java:41)
    at com.microsoft.sqlserver.jdbc.SQLServerConnection$LogonCommand.doExecute(SQLServerConnection.java:2220)
    at com.microsoft.sqlserver.jdbc.TDSCommand.execute(IOBuffer.java:5696)
    at com.microsoft.sqlserver.jdbc.SQLServerConnection.executeCommand(SQLServerConnection.java:1715)
    at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectHelper(SQLServerConnection.java:1326)
    at com.microsoft.sqlserver.jdbc.SQLServerConnection.login(SQLServerConnection.java:991)
    at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(SQLServerConnection.java:827)
    at com.microsoft.sqlserver.jdbc.SQLServerDriver.connect(SQLServerDriver.java:1012)
    at java.sql.DriverManager.getConnection(DriverManager.java:579)
    at java.sql.DriverManager.getConnection(DriverManager.java:243)
    at Main.main(Main.java:18)

Note: 用户名和密码是正确的，我已经交叉检查了它们 . 我的JDK版本是1.7更新21.当我通过更改连接字符串和驱动程序类使用 JTDS1.3.1 driver 时，如下所示：

String connectionUrl = "jdbc:jtds:sqlserver://172.16.0.4:1433/PUC;instance=mssqlserver2012;user=admin;password=admin";

Class.forName("net.sourceforge.jtds.jdbc.Driver");

它有效，但为什么不使用Microsoft JDBC Driver 4.0 for SQL Server？