无法打开登录所请求的数据库 "NewsSystem"。登录失败。
用户 'sa' 登录失败。 
说明: 执行当前 Web 请求期间，出现未经处理的异常。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: 无法打开登录所请求的数据库 "NewsSystem"。登录失败。
用户 'sa' 登录失败。

源错误: 


行 13:             string connStr = @"server=Mark-PC\sql2005;database=NewsSystem;uid=sa;pwd=3514";
行 14:             SqlConnection conn = new SqlConnection(connStr);
行 15:             conn.Open();
行 16:             string sql = "insert into Category(Name) valuse('mark')";
行 17:             SqlCommand cmd = new SqlCommand(sql, conn);
 

源文件: G:\牛腩新闻发布系统\新闻发布系统\DAL\SQLHelper.cs    行: 15 

堆栈跟踪: 


[SqlException (0x80131904): 无法打开登录所请求的数据库 "NewsSystem"。登录失败。
用户 'sa' 登录失败。]
   System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +5064458
   System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning() +234
   System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj) +2275
   System.Data.SqlClient.SqlInternalConnectionTds.CompleteLogin(Boolean enlistOK) +35
   System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, TimeoutTimer timeout, SqlConnection owningObject) +183
   System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(ServerInfo serverInfo, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, TimeoutTimer timeout) +239
   System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, TimeoutTimer timeout, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) +195
   System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) +232
   System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) +185
   System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) +33
   System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) +524
   System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) +66
   System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +479
   System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +108
   System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +126
   System.Data.SqlClient.SqlConnection.Open() +125
   DAL.SQLHelper.test() in G:\牛腩新闻发布系统\新闻发布系统\DAL\SQLHelper.cs:15
   _Default.Page_Load(Object sender, EventArgs e) +56
   System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +14
   System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +35
   System.Web.UI.Control.OnLoad(EventArgs e) +91
   System.Web.UI.Control.LoadRecursive() +74
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsy