When using a 3rd party email app. I use outlook. The authentication to the smtp server is not working. It won’t let me sign into any apps. And in outlook this causes a sign in box to pop up constantly. You also can’t send any emails. Occasionally 1 will get through. But this is not reliable. I’ve called support on Friday and I also called support yesterday and was told this would be resolved. It is not.
Resolution may take a while; it's not just flipping a switch. Seems (to me, at least) that 3rd party email apps don't play nicely with HughesNet. Have you considered going with a different email provider, such as Google?