403.14 error after updating certificate

Problem reported by Brian Henson - 3/7/2026 at 12:51 PM

Resolved

I update the SSL certificate on my Smartermail web server and now I'm getting a 403.14 error when trying to navigate to the main page. I'm also getting the same error when reverting to the old cert. I cannot login at all.

6 Replies

Reply to Thread

J. LaDow Replied

3/7/2026 at 1:56 PM

Potentially try restarting SmarterMail after the certificate change?

403.14 is usually an IIS error relating to Directory Browsing (which shouldn't be enabled) -- It sounds like IIS isn't connecting to the SmarterMail webserver proxy correctly anymore. (or SmarterMail isn't binding ports properly anymore because it doesn't like the certificate change).

Is there a bad bookmark? Are you being redirected to /interface/root#/login when you try to load the webmail?

MailEnable survivor / convert --

Brian Henson Replied

3/7/2026 at 4:16 PM

Yeah I've tried restarting both the site and the app pool, to no avail. I get the error even if I try to run the page locally on the server. I'm not seeing any redirection happen, and /interface/root#/login just leads to a 404.

J. LaDow Replied

3/7/2026 at 6:56 PM

When logged in locally to the server, can you access http://localhost:17017 ? (specifically http and not https)

If not, your SmarterMail Kestrel (web server) isn't running - which will also cause IIS to throw a 404 (or 403.14 because it can't find a "default document" to serve.

IIS is just a proxy to the built in web server in the SM service. If SM itself is what's having problems, the logs should show it.

If you can, then it's unhappy with your SSL cert - and from there, you might be able to login and re-configure the active certificate.

MailEnable survivor / convert --

Brian Henson Replied

3/7/2026 at 7:11 PM

I get error connection refused when trying localhost:17017.

If it matters, I'm using a version from 2023. The Smartermail Windows service does appear to be running.

J. LaDow Replied

3/8/2026 at 12:27 AM

If it's older than build 8747 (12/2023) then the 17017 port won't apply. http://localhost:9998 would be the "direct way in" on console - but your errors indicate this won't most likely won't work either as noted below. Still worth a try to see if it responds because that would definitely indicate something broke in the IIS configuration relating to the SSL certificate only.

If 9998 doesn't work, then there is something missing or changed in the IIS configuration that it is not seeing SmarterMail's applicaton root. Your application pool is running or you'd get a 503 (service unavailable) error. So this boils down to either the .NET process not starting up when requested by the Application pool (something like a web.config error would cause this) --

Those versions are potentially vulnerable to exploit (while not vulnerable to all the recently exposed bugs) there were still a couple bad ones that could allow the server to be completely taken over by adversaries - so be on the lookout -- you could well have much bigger problems on your hand.

MailEnable survivor / convert --

Brian Henson Replied

3/9/2026 at 6:02 PM

Marked As Resolution

Getting a refused to connect message with http://localhost:9998 as well. I am using build 8664.

I just did a re-install and that seems to have fixed it. Though the 9998 page still didn't come up.

Back to Community Threads

Please leave this box unchecked

Reply to Thread

Enter the verification text