Exchange Management Console Initialization failed upon opening

So, been messing around with SSL certificates trying to renew all your Exchange certificates and you have this as a side effect? Or, you just open Exchange Management Console and get Initialization failed message?

For the sake of people Googling:

"The following error occurred while attempting to connect to the specified exchange server

The attempt to connect to using "kerberos" authentication failed: Connecting to remote server failed with the following error message : The WinRM client sent a request to an HTTP server and got a response saying the requested HTTP URL was not available. This is usually returned by a HTTP server that does not support the WS-Management protocol. For more information, see the about_Remote_Troubleshooting Help topic."


So...

Simply open IIS and make sure your default site has an additional host header setup that matches in the error above.

I have no idea why this is caused - the default site on the machine is set to listen on all interfaces/ips and is the default site, and server name resolves to the machine - however, specifically putting the FQDN of the server in a host header fixed the issue instantly.

If you are not sure how to do this - you open IIS, go to the default site, click bindings then add and type the server there:

Hope this helps you.