Connection Error using Sprint Card

Hi After inserting the Sprint Sierra Wireless Card-850 on Win-xp OS, its giving the error of Modem not initizalizing, reinsert it. Done: 1.) Rebooted the Laptop number of times 2.) Removed and reseated the Card 3.) Took help from Sprint Tech Support, but no help. 4.) Deleted the Sprint Card listed in the Network Connection and checked. 5.) XP – Firewall is off. 6.) All telephony services, Remote connection services are on. 7.) Card always shows Green LED when inserted in the Laptop Slot.

Can you please suggest what i can do to resolve the problem.