MediaWiki extension: Server URL invalid

I setup a local MediaWiki server at and I am unable to add MediaWiki server due to URL error. I tried with and without http:// in front of the IP and even used the domain name was never able to register/add to it. Has anyone found a solution to the persisting error?

I am not an expert on MediaWiki server but may I ask where is the relationship to Libre Office?

This is a Libre Office forum.

There is an extension by default in LibreOffice Writer called Wiki Publisher to upload the content to MediaWiki. Even though I enter a correct URL yet it spits out an error saying my URL is incorrect thus the connection cannot be established.