WordPress MU

Hi all,

I'm fairly new to WPMU and tried a fresh install of 2.8.1 recently.

WPMU reports "Installation successful", but I get

Warning: call_user_func_array() [function.call-user-func-array]: First argument is expected to be a valid callback, '_show_post_preview' was given in /home/mymocla8/public_html/1online-coza/wp-includes/plugin.php on line 339

at the top of of the home page - see http://1online.co.za/ and

Warning: call_user_func_array() [function.call-user-func-array]: First argument is expected to be a valid callback, '_show_post_preview' was given in /home/mymocla8/public_html/1online-coza/wp-includes/plugin.php on line 339

Warning: Cannot modify header information - headers already sent by (output started at /home/mymocla8/public_html/1online-coza/wp-includes/plugin.php:339) in /home/mymocla8/public_html/1online-coza/wp-includes/pluggable.php on line 865

at the logon page - please see http://1online.co.za/wp-admin/

I've checked the reported files, re-uploaded them, etc. but no idea of the cause..? This is a vanilla installation - no plugins/themes added...

Please help with any suggestions!

Regards
flairJ

Having the same issue, but not on my primary blog, only on the sub blogs (with subdirectories rather than subdomains).

Tracked it down to plugin that I have installed sitewide (pagebar2). Though it could be any. Try switching them on one at a time to identify which is causing the issue.

Hi tomdebruin,

Thanks for your response. Unfortunately, as mentioned, my installation is brand new (vanilla, as downloaded from mu.wp.org), i.e. NO plugins, themes, etc. so I have nothing to deactivate. In fact, I cannot even log into wp-admin (see above)..!

Help - anyone!

Regards
flairj

Cannot modify header information usually implies a file with a blank line after the closing ?>

Also if you look they are warnings. Ideally you should have php set to send warnings/errors to a file and not to the screen.

I just went to your site and got a 500 error.

I'd grab 2.8.2 and blow everything away and try again from scratch.

I am having a similar problem on my site, FialkoffConsulting.com.

I just upgraded to WordPress 2.8.5 and Thesis 1.6.1. I also use a skin, Fresh Company and I have some functions in the wrong files, but I'm certain how to fix this.

Thanks,
Josh