I am experiencing an issue with certain emails coming from exterior services such as yahoo, and google. Specifically that requested resources can only be accessed via SSL. I found the following information on potentially resolving the issue. https://tusksoft.com/blog/posts/9/how-to-force-pages-to-not-use-ssl-in-asp-net-mvc-by-creating-a-forbidhttpsattribute
The author mentions that there are potential issues with reversing the operations of a forced HTTPS operation to allow conversion to HTTP. Can anyone please expand on these potential issues? I am curios, because this could resolve my current issue, but I do not want to create any potential vulnerabilities without understanding them more thoroughly, or preventing them entirely.
Update: to clarify the question a bit more. I am asking specifically about the potential types of threats that could be passed over a non HTTPS connection on a public facing site.