The site, J2.5.28, has been using aiContactSafe but there are issues one of those being that it has not been updated since 2012 and the forum looks dead. (As does everything else there.) However with more and more using DMARC or similar there is an issue that all the mail has to come from the servers of the hosted sites. Firebug console also shows the contact form as being insecure. aiContactSafe presumably uses phpmail as it sends the mail from the person contacting the site and not from the site itself. This is now being rejected by the site host as unknown and needs to be come from their server.
So now I am looking for a replacement that is secure, meets the DMARC requirements, and is free. Any recommendations?