Hello, THis is Tariq and i am new here. i m working on interfacing parallel port through ' C ' (OS = Win XP) . I have already successfully lighted Leds within TurboC v3.0 enviroment, using "User Port" for access to parallel port. But when i tried to run the exe file only messages appeared as programmed, but the leds doesn't blink.. i have tried a lot, and also have started userport before executing the exe file of the program.. what should i do? help me.