Register dashboard extension

[AndrewTerwiel]

I'm trying to register an Operation Dashboard extension. This is the first time I've done this as I just started learning about Dashboard yesterday. I've created a widget by following this tutorial. That all worked fine and I can add the widget to a dashboard and it works. But when I try to register the widget by following this tutorial I get an error like this:

This is my registration screen:

Does anyone know how I can fix this please?

[ChristopherOlsen]

Have you tried registering using a FQDN instead of localhost? Also, if you have enabled SSL, you could try using the https URL as well.

[AndrewTerwiel]

Thanks, Christopher, but using the FQDN did not work either.