Board Thread:Support Requests - Community Management/@comment-8429197-20170403042108/@comment-9605025-20170404001715

That is sort of what I was trying to get at. Whether or not the namespaces are configured correctly shouldn't make a difference. Page titles can have colons in them so the bottom line is that somehow the internal links are producing interwiki links when they should not be. The fact that they are producing interwiki links is odd because the only interwiki links that are supposed to be possible are listed at MediaWiki:Interwiki map which does not contain the wiki the OP mentioned.