$wpdb doesn’t like to store arrays

Don’t store serialised PHP data in the database! It can be a major security risk! When the contents of the value are deserialised, any objects get recreated and their constructors and wakeup methods run, this can be used to launch an attack. Additionally, that data can’t be search replaced, because PHP serialised strings contain values … Read more

call_user_func_array() error on front end

I’ve successfully tracked this problem by adding error_log(“wp-hook: “. print_r($the_, true)); within apply_filters in wp-includes/wp_hook.php The task is then to look at the function calls (the data inside $the_) surrounding the “PHP Warning: call_user_func_array()”. It will be the one directly ahead of the warning, but you may need to look at calls after or before … Read more

Feed could not be found

The Activity Feeds has been deprecated and no longer works after 23rd June, so this is why it would have stopped working. https://developers.facebook.com/docs/plugins/activity This is probably the nearest thing you will be able to have that is similar to the Activity Feed: https://developers.facebook.com/docs/plugins/page-plugin

WordPress Permalink 404

Change your form fields to have more unique names, specifically, title. This is an issue which was introduced when title was made a public query var in 4.4. This is seen as a bug, and will eventually be fixed, but it’s always safer to prepend any vars with a unique string to prevent these problems.

Unable to Upload Files

I figured out the issue. Under Settings > Media there is a text field saying where to upload the files to, and it was the wrong directory. I just changed it to the right one and it worked.