You may want to try installing the Kies software on your PC (with the phone disconnected) - it'll also install the right drivers for the phone. Once Kies is installed connect the phone and let Windows discover all of the right files - that may take 10 minutes; just be patient and don't fiddle with anything until Windows finishes installing drivers.but the computer is not recognising the device by USB
You said that the computer wasn't recognizing the phone - that was the purpose of installing Kies.the computer is not recognising the device by USB