Exception "Data source name not found" while connecting to an existing DSN - sql

Question

I have created an ODBC connections (both 32/64 bit) with configuration given below:
Microsoft SQL Server ODBC Driver Version 10.00.14393
Data Source Name: ODBCMSSQL
Data Source Description:
Server: .\SQLEXPRESS
Database: MedicalMarketting
Language: (Default)
Translate Character Data: Yes
Log Long Running Queries: No
Log Driver Statistics: No
Use Regional Settings: No
Prepared Statements Option: Drop temporary procedures on disconnect
Use Failover Server: No
Use ANSI Quoted Identifiers: Yes
Use ANSI Null, Paddings and Warnings: Yes
Data Encryption: No
I want to connect to local MsSQL server as given in below code snippet:
string connectionString = "Data Source=ODBCMSSQL;Initial Catalog=MedicalMarketting;Integrated Security=True";
con = new OdbcConnection(connectionString);
cmd = new OdbcCommand();
cmd.Connection = con;
cmd.CommandType = CommandType.Text;
try
{
this.con.Open();
this.tr = con.BeginTransaction();
this.cmd.Transaction = tr;
}
catch (Exception ex)
{
this.RollBack();
}
This throws an exception which has an error message as below:
ERROR [IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified
Sorry if this was too basic, but had to post for a clue because the same configuration for different ODBC connections works perfectly.

Answer 1

I found a quick fix to the problem by changing the connection string to,
string connectionString = "DSN=ODBCMSSQL";// best practice is to store this in a seperate config file.
In fact, other attributes specified (Initial Catalog, Integrated Security) are not ODBC connection string attributes, hence ignored. A full list of ODBC connection attributes can be found below.
https://msdn.microsoft.com/en-us/library/ee275047(v=bts.10).aspx