Error: 40 - Could Not Open A Connection To SQL Server

I have created a new aspx site on ‘server 1’ which connects to an sql server 200 on ‘server 2’ ‘Server 1’ is a test server and all works fine.
  I then move the site onto ‘server 3’ and receive the error below.

 

This must be a problem with ‘server 3’.
  I have installed .net version 2 on this server and there are currently no aspx sites running of this server.
  There must be smothering not configured right.
  There are other sites on the server that are talking to the SQL server.

 

Any help would be great.

Thanks

 
An error has occurred while establishing a connection to the server.  When connecting to SQL Server 2005, this failure may be caused by the fact that under the default settings SQL Server does not allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.


Exception Details:
System.Data.SqlClient.SqlException: An error has occurred while establishing a connection to the server.  When connecting to SQL Server 2005, this failure may be caused by the fact that under the default settings SQL Server does not allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)


Source Error:






An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.




Stack Trace:





 
[SqlException (0x80131904): An error has occurred while establishing a connection to the server.
  When connecting to SQL Server 2005, this failure may be caused by the fact that under the default settings SQL Server does not allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)]

   System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +735059

   System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) +188

   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) +820

   System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) +628

   System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) +170

   System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) +359

   System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) +28

   System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) +424

   System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) +66

   System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +496

   System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +82

   System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +105

   System.Data.SqlClient.SqlConnection.Open() +111

   System.Data.Common.DbDataAdapter.FillInternal(DataSet dataset, DataTable[] datatables, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior) +121

   System.Data.Common.DbDataAdapter.Fill(DataSet dataSet, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior) +137

   System.Data.Common.DbDataAdapter.Fill(DataSet dataSet, String srcTable) +83

   System.Web.UI.WebControls.SqlDataSourceView.ExecuteSelect(DataSourceSelectArguments arguments) +1770

   System.Web.UI.WebControls.Repeater.GetData() +50

   System.Web.UI.WebControls.Repeater.CreateControlHierarchy(Boolean useDataSource) +232

   System.Web.UI.WebControls.Repeater.OnDataBinding(EventArgs e) +53

   System.Web.UI.WebControls.Repeater.DataBind() +72

   System.Web.UI.WebControls.Repeater.EnsureDataBound() +55

   System.Web.UI.WebControls.Repeater.OnPreRender(EventArgs e) +12

   System.Web.UI.Control.PreRenderRecursiveInternal() +77

   System.Web.UI.Control.PreRenderRecursiveInternal() +161

   System.Web.UI.Control.PreRenderRecursiveInternal() +161

   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1360