[Klotar]

When you are at home, can you make international calls?

This may be far-fetched; but on Rogers, by default, all customers are restricted from making international (overseas) calls unless the restriction is lifted, which they will do after 6 months on request.

It may be that your carrier has something similar, where the SIM card is restricted from international use, which in turn restricts the BB from accessing data. Note that this has nothing to do with SIM card locking, device locking, international GSM frequencies or anything of that sort; it's just a matter of the account having that international restriction on it.

PS - like I say it's far fetched but not out of the question... especially if there have been no account changes other than a new device and you've travelled internationally a lot. But sometimes accounts get fubar'd by the carrier, you never know.

Worth looking into if the problem doesn't get solved by other advice here.