problema con visual web developer y coneccion a sql server

[staxman]

si la cuestion es que sql server te crea carpetas predeterminadas, eso no aparece y no tengo idea de lo q pasa :(, ya intete eso me aparece este error

Setup failed.

Exception:
Unable to connect to SQL Server database.

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Details of failure
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System.Web.HttpException: Unable to connect to SQL Server database. ---> System.Data.SqlClient.SqlException: A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)
at System.Data.SqlClient.SqlInternalConnection.OnErro r(SqlException exception, Boolean breakConnection)
at System.Data.SqlClient.TdsParser.ThrowExceptionAndW arning(TdsParserStateObject stateObj)
at System.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, Boolean trustServerCert, Boolean integratedSecurity, SqlConnection owningObject)
at System.Data.SqlClient.SqlInternalConnectionTds.Att emptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, Int64 timerExpire, SqlConnection owningObject)
at System.Data.SqlClient.SqlInternalConnectionTds.Log inNoFailover(String host, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, Int64 timerStart)
at System.Data.SqlClient.SqlInternalConnectionTds.Ope nLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance)
at System.Data.SqlClient.SqlInternalConnectionTds..ct or(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance)
at System.Data.SqlClient.SqlConnectionFactory.CreateC onnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection)
at System.Data.ProviderBase.DbConnectionFactory.Creat ePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options)
at System.Data.ProviderBase.DbConnectionPool.CreateOb ject(DbConnection owningObject)
at System.Data.ProviderBase.DbConnectionPool.UserCrea teRequest(DbConnection owningObject)
at System.Data.ProviderBase.DbConnectionPool.GetConne ction(DbConnection owningObject)
at System.Data.ProviderBase.DbConnectionFactory.GetCo nnection(DbConnection owningConnection)
at System.Data.ProviderBase.DbConnectionClosed.OpenCo nnection(DbConnection outerConnection, DbConnectionFactory connectionFactory)
at System.Data.SqlClient.SqlConnection.Open()
at System.Web.Management.SqlServices.GetSqlConnection (String server, String user, String password, Boolean trusted, String connectionString)
--- End of inner exception stack trace ---
at System.Web.Management.SqlServices.GetSqlConnection (String server, String user, String password, Boolean trusted, String connectionString)
at System.Web.Management.SqlServices.SetupApplication Services(String server, String user, String password, Boolean trusted, String connectionString, String database, String dbFileName, SqlFeatures features, Boolean install)
at System.Web.Management.SqlServices.Install(String database, SqlFeatures features, String connectionString)
at System.Web.Management.ConfirmPanel.Execute()