Hi,

I was wondering if you could help me. I own a couple Sierra Wireless 710 aircards. They have been working fine on AT&T for a quite some time. I have now switched my service to Tmobile. When I put the Tmobile sim card in the aircard, the PC gives a messages "Invalid SIM". Can these aircards be unlocked like a GSM cell phone? It has to be firmware because they sell the same cards for all GSM providers.