How can I use AutoTrader to trade multiple symbols in one Account ?
The setup is almost the same as the previous one described above, except that you only run one copy of TWS (since you only have one account), and run, say two copies of AutoTrader. Note that you can have multiple copies of AutoTrader connected to the same copy of TWS. On each copy of AutoTrader, connect to TWS. Then select a different symbol on each AutoTrader copy and now you can trade multiple symbols using one TWS account.
