Can't connect to/from SQL Server 2008 from my Windows 2008 server I have a server with:


Windows 2008 Server 
SQL Server 2008 enterprise


From my server using SQL Server Management Studio, I can't logon to any SQL Server and vice verse, I can't connect to my SQL Server from any pc/laptop.

I checked and see that, the port 1433 closed, even if I turned of firewall, I still can't connect to it.

My server name is: S143343. I have 2 sql server instances is MSSQLSERVER and S143343 (the same name with server name for replication). But I can't start S143343.

One more thing, from my server, I just connect to sql server by server name is localhost or dot (.). No way to access by computer name or IP.

Can you show me the way to solve this problems?
I'd check Services to ensure both are running - the name in Services for both SQL Servers will also confirm the instance name. On my laptop, I have MSSQLSERVER, so I can connect to that with either the machine name (LAPTOP), or with .    My other instance is called SQLTEST2, so I can connect to LAPTOP\SQLTEST2.

If that fails, go looking in both sets of binaries in Program Files. Each instance will have ERRORLOGs in the the respective log folders - that might have a clue in there, such as a login error.

Incidentally, since they are both on the same machine, ensure Shared Memory is enabled for both.