Hi @verek,

Pease delete all error logs and try the following:

If you use wpForo User Custom Fields addon, please navigate to Dashboard > Forums > Member Fields > Account Tab and click on the [SaveChanges] button.

Navigate to Dashboard > Forums > Usergroups admin page, edit the Registered group and enable the "Can allows be used as secondary" option and save it.

@robert

I don't use the custom fields plugin (nor UM and BP). 

Secondary was checked by default and makes no difference whether on or off, the PHP error is produced. Role-Usergroup Synchronization, on or off, produces the PHP error. 

The PHP error is new but the Timezone bug is not, it has been there since 1.4x.

I have set my timezone on this board to New York; if you check my profile in Wordpress users you will see it lists Abidjan as the timezone.

Posted by: VereK

This problem persists with 1.5.1.

In addition, editing a user in the Wordpress Users system throws an error.

Warning: array_filter() expects parameter 1 to be array, integer given in /home/redacted/public_html/wp-content/plugins/wpforo/wpf-includes/class-members.php on line 770
Warning: implode(): Invalid arguments passed in /home/redacted/public_html/wp-content/plugins/wpforo/wpf-includes/class-members.php on line 771
Warning: Cannot modify header information - headers already sent by (output started at /home/redacted/public_html/wp-content/plugins/wpforo/wpf-includes/class-members.php:770) in /home/redacted/public_html/wp-includes/pluggable.php on line 1219

Do you have "New User Approve" plugin installed? Could you please disable other plugins and test it again?

Similar issue with that plugin:

https://wpforo.com/community/how-to-and-troubleshooting-2/role/#post-17497

As also referenced here.

The  "secondary_groups" field is present in the wp_wpforo_profiles table - all are Null.

I do not have the New User Approve plugin installed. With all other plugins deactivated except WPforo it still produces the PHP error.