Cannot connect to Localhost on server running IIS

You will need to Regiis your .Net.

Open CMD and browse to:

"%windir%\Microsoft.NET\Framework64\v4.0.30319"

Then run the following command: "aspnet_regiis -ir"

**Update for windows server 2016/ Win10 /IIS8: No longer need to RegIIS , instead, you'll need to open "Turn windows Features on or off" Than Enable .Net Framework4.X Advanced services and "IIS/World Wide web/Application development features/ASP.Net 4.X"

I was struggling with a similar problem - I didn't have any connections and couldn't connect to even localhost with IIS.

Turns out I had forgotten to open IIS as an administrator. That fixed the problem.