error: 26 - Error Locating Server/Instance Specified

Hi Experts,

I have been running applicatin on SQL Express but as my database started becoming bigger and I found my application running very slow, I started to Switch from Express to SQL 2008. I Re-inStalled Entire Windows 2008 Server, Installed SQL 2008 (Installed as Instance Name :- MSSQLSERVER), Changed the Connection String from

Data Source = .\SQLExpress to Data Souce = SERVERUS1
(SERVERUS1 is the computer name. I use the same name to connect to SQL server using Management Studio)

Error :-

eption Details: System.Data.SqlClient.SqlException: 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: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)

Now it shows me this Error. Did I make mistake while typing in the ConnectionString?
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You should include the instance name in the data source, like so:


Make sure that you have connectivity for remote connections.  (If you are connecting with Management Studio remotely, then no problem.)

How to: Enable Remote Connections on SQL Server

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