用户“administrator”登录失败

string strconn = "data source=FE1DC073281F44D;initial catalog=Northwind;Persist Security Info=true;user id=administrator;password=fengyun";
SqlConnection conn = new SqlConnection(strconn);
conn.Open();
string strsql = "insert into userinfo values('" + txtname.Text + "','" + txtPwd.Text + "','" + txtmail.Text + "')";
SqlCommand mycommand = new SqlCommand(strsql, conn);
mycommand.ExecuteNonQuery();
lblMessage.Text = "注册成功，请重新登录";

//FE1DC073281F44D是我的sql server 2000服务器的名字，数据库名字是Northwind，安全性中选择sql和windows认证，我在企业管理器中查看到数据库可以创建成功，用的编程环境是visual stdio 2005 asp.net，建立的是一个注册提交的页面。到底是什么问题，大家解释一下！按“提交”后出现错误页面如下：

用户 'administrator' 登录失败。
说明: 执行当前 Web 请求期间，出现未处理的异常。请检查堆栈跟踪信息，以了解有关该错误以及代码中导致错误的出处的详细信息。

异常详细信息: System.Data.SqlClient.SqlException: 用户 'administrator' 登录失败。

源错误:

只有在调试模式下进行编译时，生成此未处理异常的源代码才会显示出来。若要启用此功能，请执行以下步骤之一，然后请求 URL:

1. 在产生错误的文件的顶部添加一条“Debug=true”指令。例如:

<%@ Page Language="C#" Debug="true" %>

或:

2. 将以下的节添加到应用程序的配置文件中:

<configuration>
<system.web>
<compilation debug="true"/>
</system.web>
</configuration>

请注意，第二个步骤将使给定应用程序中的所有文件在调试模式下进行编译；第一个步骤仅使该特定文件在调试模式下进行编译。

重要事项: 以调试模式运行应用程序一定会产生内存/性能系统开销。在部署到生产方案之前，应确保应用程序调试已禁用。

堆栈跟踪:


[SqlException (0x80131904): 用户 'administrator' 登录失败。]
System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +173
System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) +199
System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj) +2402
System.Data.SqlClient.SqlInternalConnectionTds.CompleteLogin(Boolean enlistOK) +34
System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, Int64 timerExpire, SqlConnection owningObject) +223
System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(String host, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, Int64 timerStart) +371
System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) +184
System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) +193
System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) +502
System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) +28
System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) +429
System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) +70
System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +512
System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +85
System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +89
System.Data.SqlClient.SqlConnection.Open() +160
_Default.btnSubmit_Click(Object sender, EventArgs e) +42
System.Web.UI.WebControls.Button.OnClick(EventArgs e) +75
System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +97
System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +7
System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +11
System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +33
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +4921