Enable the SQL Server Browser service
If we are running sql server 2005 by using instance name and we are not using specific port number in connction string we need to enable sql server browser service to allow remote connctions. For example if you are using computername\sqlexpress you need to enable sql server browser service.
One important thing while doing enabling sql server browser service is it is increasing security risk and making the computer or network to more vulnerable to attacks by malicious programs or malicious users such as viruses. I recommended you to follow this only if you really requires this.
Steps to enable the SQL Server Browser service
1. Click start->programs->microsoft sql server 2005-> configuration tools->
sql server surface area connection.
2. In sql server surface area configuration page click Surface Area Configuration for Services and Connections.
3.In Surface Area Configuration for Services and Connections change sql server browser startup type to automatic. click apply
4. Click start-OK
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