“Unexpected Error 0×8ffe2740 Occurred” when trying to start a Web Site in IIS

Today I was surprised by IIS refusing to start at my computer due to cryptic:

Unexpected Error 0×8ffe2740 Occurred

Quick googling pointed Microsoft Knowledge Base Article KB816944 saying:

This behavior may occur if a port conflict exists on the system. By default, IIS uses port 80 for HTTP communication. If an application other than IIS is running and is using port 80 on the same IP address, you may receive the error message when you try to use IIS Manager to start the Web site.

OK. But which application dares to use port 80 at my computer?

The culprit – Skype. Sometimes it uses ports 80/443…

To disable it:

1. Open Skype
2. Select Tools / Options
3. Select “Connection” tab
4. Disable “Use port 80 and 443 as alternatives for incoming connections”

Now IIS can start a web site.