Windows 7 Mobile Modem

[Myobi]

Hello, I installed windows 7 this weekend... until now everything was great. Today I went to school and tried to connect to the internet through my mobile modem, the problem is it keeps dectecting the modem and then it just vanish's... then it detects it again! and just keeps doing it. It seems its something related to the "Data Interface", any suggestions? =/