I am working on a site that has only text articles, and I am not making use of comments, archives, trackbacks and other features.
How can I make so these pages show a 404 not found error? I am not linking to those pages from my theme but it happened to me in the past that google crawled duplicated content from archives pages.
To make it more clear, my website is just a homepage with an articles list (posts), posts don’t have comments or anything, just the text.
Two separate parts to consider: comments / trackbacks and archive pages.
If you don’t enable comments and trackbacks, no links will exist for them, thus a 404 or redirect won’t be necessary. You can’t link to something that isn’t there 🙂
As for the archive pages, WP will create those whether you want them or not. If you won’t want people going to them at all (which would be a bad user experience IMHO) then you can set a manual redirect for each category & tag you create to go back to the home page. However, a better bet is to set those pages to noindex / noarchive using either the SEO controls in your theme framework (if they exist) or a plugin such as Yoast’s SEO plugin.