Was told this is related to attachment plugin: running 1.7.1 and latest attachment plugin. Random members when logging in ( or when visiting their profile page ) will get an e500 and this error. When I deactivate the attachment plugin, the error is not seen.
Error details:
Type: Error
Message: Argument 1 passed to GROUPS_BOL_Service::getGroupUrl() must be an instance of GROUPS_BOL_Group, null given, called in /var/www/vhosts/httpdocs/dd/ow_plugins/attachments/classes/groups_bridge.php on line 62 and defined
File: /var/www/vhosts/httpdocs/dd/ow_plugins/groups/bol/service.php
Line: 387
Myself included just now.