since i have upgraded my Wordpress MU to the latest version (2.9.1.1), comments do no longer work - instead i get a 404 page. i'm aware a similar behaviour was reported here many times, but none of the solutions work. before i go into that, i want to sum up some other things that stopped working.
regarding the comments:
-logged in as administrator comments work
-other logged in users get 404
-guest users get 404
i have tried the following to get it working again, all without success:
-install a new wordpress (tried the normal and the mu version) and import the data - no change
-sync the comments with intense debate and disqus - not working (disqus works partly)
i came across this bug on both wordpress forums and got the suggestions of changing my permalink structure (there has been an issue with the ending slash), disable comment paging and nesting, changing the permission of comments.php
what i can tell is, that wordpress mu does not work since the upgrade - though i incidently use a new theme since that day. i think i followed all steps to rule out that my comment is to blame for this:
-commenting works on a new wordpress installation with no imported data
-the 404 also happens with other theme (including both defaults)
-i tried it with and without plugins enabled
the last thing i did was to manually copy a new version of wordpress mu over my existing installation. since then, i get an error rather than a 404 page:
Warning: get_object_vars() expects parameter 1 to be object, null given in /path.to.my.blog/wp-includes/comment.php on line 161
Warning: Cannot modify header information - headers already sent by (output started at /path.to.my.blog/wp-includes/comment.php:161) in /path.to.my.blog/wp-comments-post.php on line 85
Warning: Cannot modify header information - headers already sent by (output started at /path.to.my.blog/wp-includes/comment.php:161) in /path.to.my.blog/wp-comments-post.php on line 86
Warning: Cannot modify header information - headers already sent by (output started at /path.to.my.blog/wp-includes/comment.php:161) in /path.to.my.blog/wp-comments-post.php on line 87
Warning: Cannot modify header information - headers already sent by (output started at /path.to.my.blog/wp-includes/comment.php:161) in /path.to.my.blog/wp-includes/pluggable.php on line 868i did not found anyone else reporting such behaviour, hence i'm VERY clueless on how to fix this issue. being unable to find out what was the last version of wordpress mu, i can't go back to it to see if that's working.
any help is most appreciated!
