Can't upgrade plugins automatically, class not found after upgrading to 3.3

Try:
– switching to the Twenty Eleven theme by renaming your current theme’s folder in wp-content/themes and adding “-old” to the end of the folder name using FTP or whatever file management application your host provides.

– resetting the plugins folder by FTP or phpMyAdmin.

– re-uploading all files & folders – except the wp-content folder – from a fresh download of WordPress.

Themes can (and do) affect the back end of your site (otherwise how would they apply custom theme settings?). Ditto plugins. Do try the usual tests ??

I switched themes, still had the problem.

I deactivated all the plugins (both through the admin interface and by renaming the directory), still had the problem. It actually got worse after I did this; instead of saying “Upgrade plugins” in the right pane of the admin, it went whitescreen on me with the following error:

PHP Fatal error: Class 'Plugin_Upgrader' not found in /path/wp-admin/update.php on line 62, referer: https://example.org/wp-admin/plugins.php?activate-multi=true&plugin_status=all&paged=1&s=

I replaced all the files and folders except wp-content with a fresh download. (You should remind people to copy over wp-config as well.)

One other bit of information: I had to do the fix detailed in https://www.ads-software.com/support/topic/wp-28-fresh-install-fatal-error-call-to-undefined-function-wp_dashboard_setu?replies=24 where ABSPATH has to be removed.

I look forward to further suggestions. Incidentally, do either of you hang around in IRC?

What happens if you remove that fix?

Then I get a whitescreen error at /wp-admin with the following in the log:

PHP Fatal error: Call to undefined function wp_dashboard_setup() in /path/wp-admin/index.php on line 15

Are you deleting the old folders when you upload the fresh copies?

What I’m doing with the ‘fresh’ copy of WordPress is copying over the wp-content folder and wp-config.php file to the “new” copy and running that. So no, I’m not deleting the old folders, but the ‘new’ folders are pristine.

I know this might sound a little bizarre but try deleting the wp-admin and wp-includes folders first. Plus all of the WP files in the root with the exception of your .htaccess and wp-config.php files.

I unzipped a new copy of wordpress and moved over a directory and a file. The wp-admin and wp-includes directories are brand new and have not been modified at all. Is there anything else we can try before I completely blow up a production blog?

Can you open your copy of wp-admin/includes/dashboard.php and check that the wp_dashboard_setup function is defined on line 16?

Yep. Line 16:

function wp_dashboard_setup() {

Is there any other information I can provide?

Sorry – not had much time to spend here today. But I have to admit, I’m pretty stumped by this one. How many lines do you have in wp-admin/includes/dashboard.php? Mine has 1363.

Yup, 1363 lines.

I was finally able to come back to this yesterday. It turns out to be a problem with APC. Turns out that I had the following line in my php configuration:

apc.include_once_override = 1

Changing this to

apc.include_once_override = 0

fixed the problem. Now I can update plugins automatically. php version is 5.2.17, APC is 3.1.9, WP 3.3.1. (Yes, I know we should be on php 5.3. No, I don’t have the resources to test all our sites.)