06-21-2014 12:29 AM
Hi and Welcome to the Community!
There are a few reports of some carriers restricting the use of BIS-related services to only via their data network, and blocking it via WiFi. I've no idea if your carrier is one of them...you would have to ask them.
However, in all cases, an active BIS subscription from a carrier is required to use BIS-related services, which includes email, even if you use those services via WiFi. So, if you don't have a BIS subscription, then that explains why you can't do what you describe -- quite simply, you can't use services you don't pay for.
Good luck and let us know!