Shared Memory, TCP, Named Pipes are enabled. SQL Server Browser service is running.

I tried with

EXEC master.dbo.sp_addlinkedserver @server = N'TestServer1', @srvproduct=N'SQL_SERVER', @provider=N'SQLNCLI10', @datasrc=N'xxxxxxx'

But still getting the same error

OLE DB provider "SQLNCLI10" for linked server "TestServer1" returned message "Login timeout expired".

OLE DB...

EXEC master.dbo.sp_addlinkedserver @server = N'TestServer', @provider=N'SQLNCLI', @datasrc=N'ServerName'

This is how I create the linked server. I am able to access the data through the linked server