Hi Nate! The Server Essentials setup isn't something I have experience with, but I have seen my fair share of binding issues in IIS. What I'm thinking is happening here is that Server Essentials is adding these bindings and possibly redirects for those bindings to facilitate something it is doing, and this is causing trouble with SmarterMail because Windows isn't seeing a Default Web Site entry in IIS. Did you remove that default site when you configured SmarterMail on this server? With that being said, adding bindings to your SmarterMail site should not cause issues with existing bindings, so I also wanted to have you try accessing SmarterMail from http://localhost:9998 from the server itself when this happens. Do you get an error there as well, or only on the public bindings/ports? 

When installing the Server Essentials, it did create a site in IIS named "WSS Certificate Web Services", so I am not sure why it did not inset the bindings into that site. Because it did in fact insert the bindings into the SmarterMail site, it stopped the site from running because of a conflict in bindings (port 80) within the other site that is being hosted. Once I deleted the additional bindings, I was able to get SmerterMail back up and running. When I have a little more time to work on this issue, I will take the bindings that were added to the SmarterMail site, and enter them manually into the Server Essentials site, and hopefully at that point, Server Essentials will start working and remote PC's will be able to connect and begin backing up. I find it hard to believe that it would be impossible to run SmarterMail and Server Essentials on the same server. I will keep you posted as to the outcome. Thanks for following up.

You're very welcome Nate, let me know how it goes! Do you have a critical need for the server essentials components or is this just part of your deployment process? I wonder if you might be able to install the individual roles instead of doing it all in one go, and thereby avoid its configuration changes to the IIS site. Worst case I'd think it should be possible to configure server essentials to use other ports (maybe 8080 in this case) and let SmarterMail continue using port 80?

I did try to just add the binding for SE in IIS, but that didn't work. I guess my next try will be to un-install SmarterMail and then install SE - then re-install SmarterMaill and see if that works, Kind of a PITA if you ask me, but we will see.

Oof, yeah that sounds like its definitely giving you a hard time! We typically install on Windows Server 20xx Standard or Datacenter editions, and most of the environments I've worked on have used the same. I wonder if there might be some limitations in there somewhere that we're hitting. I'm going to see if I replicate with the same role deployed. It may be some time before I can get that finished but I'll keep you posted!

I got a server set up for this today Nate, and should have some results post-install of those services sometime tomorrow with any luck. I'll let you know how I make out on this end.

I attempted to get those roles installed after setting up a SmarterMail server and the configuration portion of the role install fails repeatedly, even though I've restarted the machine since installing the role per its request. In looking at the role service components I see it includes one called Email Service, so I wonder if one these might be failing startup due to some overlap in the services the role is offering versus what IIS/SmarterMail is offering. 

That is likely the issue. I didn't install any Microsoft email roles when I deployed this server because I knew I would be using SmartMail, which is much friendlier and featue packed than Exchange. I'm impressed, there is a lot of work involved in deploying a server just to figure out this SE issue - THANKS!

Well we're happy to hear you're enjoying SmarterMail! :-) You're very welcome to the assist - happy to help out. Please don't hesitate to reach out if you need anything in the future.