In a very few cases it could be possible that pages and posts can’t be opened after you publish them. Instead of seeing the Page you will see a broken page or a 404 error message. You could search hours for the source, as I did once, or you do this:
- Download, install and activate the Force Publish Plugin https://wordpress.org/plugins/force-publish-schedule/
- Open it, select page(s) from the list and click Publish.
- Try again to open you pages or posts in frontend. The problem most likely will be solved.