vs2010连接sql2005的有关问题

vs2010连接sql2005的问题
win7系统，装的vs2010旗舰版，数据库sql server 2005 ,跟牛腩新闻发布系统视频在学，刚看到第6讲编写SQLHelper时，一步一步跟着视频写的代码，视频中写好后在浏览器中查看没有出错，而我在浏览器中查看就出错了，下面是出错的信息

C# code

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 includeStagesAfterAsyncPoint) +2207

C# code

 public class SQLHelper    {        public int test()        {            string connStr = @"server=Mark-PC\sql2005;database=NewsSystem;uid=sa;pwd=3514";            SqlConnection conn = new SqlConnection(connStr);            conn.Open();            string sql = "insert into Category(Name) valuse('mark')";            SqlCommand cmd = new SqlCommand(sql, conn);            int res = cmd.ExecuteNonQuery();            conn.Close();            return res;        }    } 
 

XML code

<configuration>  <connectionStrings>    <!--<add name="ApplicationServices"         connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|\aspnetdb.mdf;User Instance=true"         providerName="System.Data.SqlClient" />-->    <add name="connStr" connectionString="server=.\sql2005; database=NewsSystem; uid=sa; pwd=3514"/>  </connectionStrings>  <system.web>    <compilation debug="false" targetFramework="4.0" />    <authentication mode="Forms">      <forms loginUrl="~/Account/Login.aspx" timeout="2880" />    </authentication>    <membership>      <providers>        <clear/>        <add name="AspNetSqlMembershipProvider" type="System.Web.Security.SqlMembershipProvider" connectionStringName="ApplicationServices"             enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false"             maxInvalidPasswordAttempts="5" minRequiredPasswordLength="6" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="10"             applicationName="/" />      </providers>    </membership>    <profile>      <providers>        <clear/>        <add name="AspNetSqlProfileProvider" type="System.Web.Profile.SqlProfileProvider" connectionStringName="ApplicationServices" applicationName="/"/>      </providers>    </profile>    <roleManager enabled="false">      <providers>        <clear/>        <add name="AspNetSqlRoleProvider" type="System.Web.Security.SqlRoleProvider" connectionStringName="ApplicationServices" applicationName="/" />        <add name="AspNetWindowsTokenRoleProvider" type="System.Web.Security.WindowsTokenRoleProvider" applicationName="/" />      </providers>    </roleManager>  </system.web>  <system.webServer>     <modules runAllManagedModulesForAllRequests="true"/>  </system.webServer></configuration>