I had been working on my solution for a year when suddenly the projects stopped working at the usual HTTPS port. I assumed this had something to do with Stacker, which I uninstalled. No matter what, the HTTPS port would not start to work and the solution had two ports when running locally on IIS Express.
Maybe due to the use of Stacker, but after two hours of troubleshooting, I found the problem to be easy to solve. Checking in the project properties I found a configuration error:
The Development Server properties were off, now having SSL Enabled = False and two urls, one for non-SSL and one for SSL.
I also had to go to the Solution’s .vs / config folder, in which I fixed applicationhost.config due to erroneous configuration of my web application. Then I removed the IISExpress folder from My Documents to force a re-install.
The final magic was to install the certificate:
C:\Program Files (x86)\IIS Express>iisexpressadmincmd setupsslurl -url https://localhost:4544 -useselfsigned