Hi, That is my mistake, I find that I should passing the host ip without any single quotes. Thanks for your help. incorrect: ./ibtest.py --host '192.168.0.21' --port 4001 --data0 EUR.USD-CASH-IDEALPRO --resample --timeframe Seconds --compression 1 correct ./ibtest.py --host 192.168.0.21 --port 4001 --data0 EUR.USD-CASH-IDEALPRO --resample --timeframe Seconds --compression 1 Best Regards Barry