Okay, that's weird. On entries on my WordPress blog that have comments, the permalinks aren't working. If there are no comments on an entry, the permalink works just fine.
And that's the "Comments" link, the permalink for the post in the title, and even the "View" links from the Admin dashboards.
I get (on Chrome):
NO DATA RECEIVED
Unable to load the webpage because the server sent no data.
Error code: ERR_EMPTY_RESPONSE
(IE gives me "This page can’t be displayed".)
E.g.:
Works: https://hill-kleerup.org/blog/2014/11/07/vader-un-voiceovered.html
FUBAR: https://hill-kleerup.org/blog/2014/11/07/farewell-to-the-mentalist-soon.html
This seems to have come up since I updated (last night) to WP 4.0. But all of my other 4.0 sites are working just fine.
A quick check on Google doesn't reveal anything obvious. Anyone ever see something like that?
Did you reset perms links. This solves a lot of problems. Also check that your upload folders are set right. I had to do both of these things when I updated to 4
+Michelle Norton I wasn't sure how that would affect permalinks for uncommented posts, but not for commented ones, but I gave it a try, and it didn't fix things.
Aha. Problem solved (with a bit more Googling):
This WP forum thread (https://wordpress.org/support/topic/40-upgrade-makes-comments-disappear) indicated the problem was an incompatiblity with the Thesis theme, which led to this thread (http://diythemes.com/forums/showthread.php?100176-Thesis-1.8.5-WordPress-4.0-Comments-Not-Showing) indicating how to fix it. All seems well now.