sql server - An unhandled exception of type 'System.Data.SqlClient.SqlException' occurred in System.Data.dll in Winform -

i'm using sql server 2014 , code:

void loadproductsinfor() {      sqlconnection con = new sqlconnection();      con.connectionstring = @"server=.\sqlexpress;database=cnet_block3;uid=sa;pwd=123456;integrated security=true";       con.open();       sqlcommand cmd = new sqlcommand();      cmd.connection = con;      cmd.commandtype = commandtype.text;      cmd.commandtext = "select * products";       sqldatareader dr = cmd.executereader(); // exception happens here       while (dr.read())      {          datagridview1.rows.add(dr[0].tostring(), dr[1].tostring(), dr[2].tostring(), dr[3].tostring(), dr[4].tostring(), dr[5].tostring(), dr[6].tostring(), dr[7].tostring(), dr[8].tostring(), dr[9].tostring(), dr[10].tostring());      }       dr.close();      con.close(); } 

i tried many things didn't work.