我希望使用工具MySql Migration Toolkit将数据库从Sql Server 2008迁移到MySql，但是当工具建立数据库连接时，我收到此错误：
Connecting to source database and retrieve schemata names.
Initializing JDBC driver ...
Driver class MS SQL JDBC Driver
Opening connection ...
Connection jdbc:jtds:sqlserver://localhost:1433/Northwind;user=sa;password=;charset=utf-8;domain=
The list of schema names could not be retrieved (error: 0).
ReverseEngineeringMssql.getSchemata :Login failed for user 'sa'.
Details:
net.sourceforge.jtds.jdbc.SQLDiagnostic.addDiagnostic(SQLDiagnostic.java:365)
net.sourceforge.jtds.jdbc.TdsCore.tdsErrorToken(TdsCore.java:2781)
net.sourceforge.jtds.jdbc.TdsCore.nextToken(TdsCore.java:2224)
net.sourceforge.jtds.jdbc.TdsCore.login(TdsCore.java:599)
net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:331)
net.sourceforge.jtds.jdbc.ConnectionJDBC3.<init>(ConnectionJDBC3.java:50)
net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:178)
java.sql.DriverManager.getConnection(Unknown Source)
java.sql.DriverManager.getConnection(Unknown Source)
com.mysql.grt.modules.ReverseEngineeringGeneric.establishConnection(ReverseEngineeringGeneric.java:141)
com.mysql.grt.modules.ReverseEngineeringMssql.getSchemata(ReverseEngineeringMssql.java:99)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
com.mysql.grt.Grt.callModuleFunction(Unknown Source)
在SQL Server中我没有连接数据库的用户和密码（Window Authentication）所以在SQL的连接参数中我插入Username字段=“sa”并留空字段密码。
您知道为什么我会收到此错误以及如何解决此问题？
非常感谢你的关注。
干杯：）