Original Title: Bounced email to Cuba.

I have tried repeatedly to send an email to someone in Cuba, from my laptop and my iPhone. The bounced email on my laptop says:

*** Email address is removed for privacy ***' on 1/24/2016 10:45 AM

            Server error: '554 5.1.8 - Invalid email domain for: *** Email address is removed for privacy *** [R0109007]'

I replaced the real surname with x's for privacy.

Does anyone know what the problem might be?

Thanks,

Jo