microblogposter invalid redirect_uri

I have followed the help here http://efficientscripts.com/help/microblogposter/linkedinhelp

And I added an URL http://your-blog-url/wp-admin/options-general.php?page=microblogposter.php

replacing your-blog-url with my website but I still get the error

“invalid redirect_uri. This value must match a URL registered with the API Key.”

when I try to authorise the app from the plugin page.

I have the same problem this guy has:
https://wordpress.org/support/topic/linkedin-authorization-issue