there are 2 available mobile broadband service qtel is providing.

1. Shahry mobile broadband

2. Prepaid mobile broadband

When you plugin your USB device to your computer. It will install the driver and interface.

Make sure that when you connect select "Prepaid mobile broadband". otherwise it will not connect.

Also check the APN settings which is usually "web.qtel" or "gprs.qtel"

This is what i did when i purchased my prepaid broadband who at 1st did not work but thanks to the nice Qatari lady in Qtel Alkhor, she taught me the procedure.