Last modified: 2007-01-31 16:20:46 UTC
this page and others, I imagine, links to a page which no longer exists: http://en.wikipedia.org/w/index.php?title=HMS_Northumberland_%281798%29&action=edit
Content issues aren't bugs in the software, and should be raised on the discussion pages of the relevant articles.
red links are part of the wiki concept. red links are your friend: they show what is missing, and invite to add it.