ISession session = null;

session = Program.NHFactory.OpenSession();

IList emp = session.CreateQuery("select e.Emp_id, e.Fname, e.Minit,
e.Lname from Employee e").List();

//Employee is a Persistent Class (employee is a SQL Server 2000 table)

Using the above code, I am specifying the datasource of a datagridview as "emp". I am NOT able to get the values for any column/rows by specifying the aliases (Emp_id, Fname, Minit, Lname) as datapropertyname. I am not getting any error but the datagridview is NOT at all populating any values. But "emp" is getting populated correctly.

Any help to solve this problem would be greatly appreciated.

You are doing a "scalar query", which will return an object[], not an IList of the type you are expecting. If you want to use scalar queries, please check this thread and see if that will solve your problem.