What carrier would make no real difference. It is the device that does. Depending on the type of files you are trying to open, then may not be able to be opened on that device as it may not support them. If that is the case, then you would probably need to access them on a computer. If you can't, then you would need to contact the place you got it from and see if they can either send you the information in a file type that your phone can access, or refund your money.