I have 2 HDTV receivers with Dish. Not Duo. But 2 separate receivers and separate cards. I used to have Dish network at my store. Now cancelled subscription. Can I use One of the receiver from Home and use it at the store, Without any issues?
Not legally. Your home subscription os only for one service address. The business is most likely a separate address.
Becasue it is a business there are other considerations, in that content is often licensed differently for business establishments (especially if customers will consume the content), you may get into legal trouble using a residential subscription in your business.
