cant connect laptop to interceptor

[Ef_falcon_95]

hi all

having trouble connecting my laptop to my interceptor.it has all the correct wires installed correctly. im using a RS232 (9pin) to usb cable.
im running windows 7 but have xp mode installed which is running the interceptor tuning program.

when i click to go online it says cant find com port ?? ive tried most of the com ports but now have to idea what to do, i turn the key to ignition on, is there a way i can tell its actually turned on ??

thanks