Problem to access the SQL Server I have SQL Server 2005 which is installed on server machine.

I was working fine on SQL server before I change the server machine IP. I changed server machine IP to host the Web Service on it.

But now when I enter the Login and Password information SQL Server displays this error message:


  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) (Microsoft SQL Server, Error: 2)


I also tried to remove Server machine IP, Still I can't able to access the SQL Server.
My all database stucked in it. Or can I recover my SQL server database?
Make sure SQL Server Service is running
If a named instance, make sure SQL Server browser service is running
Make sure SQL Server is configured to allow remote connections
Examine the SQL Server error log for messages confirming that SQL is listening on the  expected network interfaces and ports
Test server connectivity with PING from the client machine
Test port connectivity using TELNET or PowerShell to the server and port (from step 4) from the client machine.  For example

a. TELNET  1433

b. PowerShell: 


1433 | % { echo ((new-object Net.Sockets.TcpClient).Connect("YourServerName",$_)) "server listening on TCP port $_" }


Check firewall settings if step 5 or 6 connectivity test fails


For further read below forum discussing the same which would be helpful to you for troubleshooting :

https://stackoverflow.com/questions/18060667/cannot-connect-to-server-a-network-related-or-instance-specific-error