@Steven - I think this might be either a Base URL issue or a problem involving CSP as Emily has pointed out. If this is an issue with CSP, I believe it might be stemming from the redirect from HTTPS to HTTP and redirect from port 443 to port 9996. Do you have all of the possible hostname configurations added to your CSP lists? Absent that, I believe the base URL might in fact be the issue. This is set within Settings>Management Interface and you may have better results setting that to your HTTP hostname on port 9996, though I recommend completing a backup beforehand just to be safe! If you end up needing some deeper review done on this please don't hesitate to submit a ticket with us. Have a good one!
Kyle Kerst
IT Coordinator
SmarterTools Inc.
www.smartertools.com