ConnectionString in app.Config not working

Question

In my winform project, I have a connection string to connect to SQL. I have this connection in the app.config file as follows:

 <connectionStrings>
  <add name="MyConnectionString" providerName="System.Data.SqlClient"
        connectionString="Server=(localdb)\\v11.0; Integrated Security=true; AttachDbFileName=C:\\Folder\\mydataBaseName.mdf;Connect Timeout=15;Encrypt=False;TrustServerCertificate=False" 
   />

and I get the connection:

string config = ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString;
//and then
 using (SqlConnection conexao = new SqlConnection(config))
        {
            conexao.Open();
         .......
         .......
        }

When I launch the application, I get an error: "An unhandled exception of type" System.Data.SqlClient.SqlException "occurred in System.Data.dll"

But if I call the connection string directly from the code (without using app.config), everything is fine.

string config = "Server=(localdb)\\v11.0; Integrated Security=true; AttachDbFileName=C:\\Folder\\mydataBaseName.mdf;Connect Timeout=15;Encrypt=False;TrustServerCertificate=False";

Any ideas how to solve the problem?

Thanks Leonor

Answer 1

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