求助,.NET链接数据库问题
原先好好的,一直运行很成功,今天一点调试就出现这样的问题,我检查了,不管是字符连接,还是数据库TCP都是打开的,请大侠指点
System.Data.SqlClient.SqlException: 在建立与服务器的连接时出错。在连接到 SQL Server 2005 时,在默认的设置下 SQL Server 不允许进行远程连接可能会导致此失败。 (provider: 命名管道提供程序, error: 40 - 无法打开到 SQL Server 的连接)
在 System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection)
在 System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj)
在 System.Data.SqlClient.TdsParser.Connect(Boolean& useFailoverPartner, Boolean& failoverDemandDone, String host, String failoverPartner, String protocol, SqlInternalConnectionTds connHandler, Int64 timerExpire, Boolean encrypt, Boolean trustServerCert, Boolean integratedSecurity, SqlConnection owningObject, Boolean aliasLookup)
在 System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance)
在 System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance)
在 System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection)
在 System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options)
在 System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject)
在 System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject)
在 System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject)
在 System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection)
在 System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory)
在 System.Data.SqlClient.SqlConnection.Open()
在 com.company.dzr.bookShop.bookShopDAL.DBHelp.RunSQLReturnDT(String sql) 位置 D:\我的文档\桌面\booksShop\bookShopDAL\DBHelp.cs:行号 212
select * from categories