Unfortunately I’m struggling with the same issue. Before, I used Mailchimp and didn’t have any problem with forwarding my newsmail through outlook. Recently, I implemented HubSpot because of its professional CRM features, but honestly I’m really disappointed since forwarded newsmails have completely lost the original design. This gives a very bad impression. I can’t understand why a professional system like HubSpot is way behind a simple system like Mailchimp regarding the feature of forwarding newsmails.