无法连接到Visual Studio中的SQL Server

Question

I tried to make a mail service with connection to the SQL Server, when I reached

 con.open(); //where con is the sqlconnection string

It said:

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)

I tried to enable tcp/ip, checked all services and it were enabled! and even I gave permissions to own user (me). Still it didn't work!

What can I do now ?

Answer 1

I am solving that problem by opening Services then start running SQL Server (SqlExpress) service.