Best advice is to walk through "WICED CYW20706 Kit Guide" diligently.
From your description, there appeared to be some issue recognizing the board. Ensure that the
FTDI usb-to-serial comm driver is installed properly. For the first time installation, let Windows
installed this automatically. It may take a while though. Subsequently you may want to verify that
the two ports are indeed detected properly via the Device Manager. Occasionally it is not detected
by Windows for unknown reasons.
I do not use USB hub and I always use the same USB port on my laptop for my work.
And I use Win7 32bits.
i followed your advice to reinstall the driver . This time i let windows installed this automatically. After doing this, it actually began to work. But several times later, the same problem appeared.
I also do not use USB hub and i use Win7 64bits.
When you say device was not detected, are you able to see the device in the device manager or not?
Did you try "recovering" the board when you were not able to program?