Sql-server – Can’t connect to Sql Server 2008 named instance

connectionsql serversql-server-2008windows-server-2008

I just installed Sql 2008 Express on a new server running Windows Server 2008. I know Sql is working properly, because I can connect to the db fine locally, on the server. I cannot connect to it from a client machine though, neither by IP address nor by machine name (iporname\instance).

I know I have the correct IP address, because I am RDCing into the server to perform all this configuration and setup, and if I ping the server name, it is resolving to the correct IP address as well.

On the server, I have set up an inbound firewall exception allowing all traffic on any port on any protocol to sqlservr.exe.

In SSMS, in server > Properties > Connections Allow remote connections to this server is enabled. In Sql Server Configuration Manager, TCP/IP is enabled in both the Protocols for <instance> and the Client Protocols sections.

I looked in the Windows logs, but don't see anything about connections being denied or dropped.
As far as I can see, I have everything set right, but cannot connect from a client machine. The client CAN connect to other Sql 2008 Express servers okay, so I know the client configuration is correct.

Any ideas where else I can look for info of what/where/how this connection is dropping, greatly apprecaited!

The error being returned by the client is:

**TITLE: Connect to Server**

Cannot connect to [MY.IP.ADD.RSS]\[MYINSTNAME].

ADDITIONAL INFORMATION:

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 SQL Server is configured to allow remote connections. 
(provider: SQL Network Interfaces, error: 26 Error Locating Server/Instance Specified)
(Microsoft SQL Server, Error: -1)

Best Answer

You need to start the SQL Browser service, and configure the firewall to all UDP 1434 traffic to the SQL Browser service. This service is what allows the SQL client software to figure out which TCP port the named instance is listening on.