Call to a member function assign() on null on new user submision

Thanks.
A quick in between soltution is to deactivate the DPcalende user plugin.
I will inform the developper too and hope they will pick it up

Thanks very much for looking at the problem. Here is a log I captured while adding a dummy member to community builder: everything.php ( ASCII text )#
#<?php die('Forbidden.'); ?>
#Date: 2024-09-03 04:59:04 UTC
#Software: Joomla! 5.1.4 Stable [ Kudumisha ] 27-August-2024 16:00 GMT

#Fields: datetime priority clientip category message
2024-09-03T04:59:04+00:00 CRITICAL 1.146.150.194 error Uncaught Throwable of type Error thrown with message "Call to a member function assign() on null". Stack trace: #0 [ROOT]/libraries/src/Plugin/CMSPlugin.php(289): DigitalPeak\Plugin\User\DPCalendar\Extension\DPCalendar->onUserAfterSave()
#1 [ROOT]/libraries/vendor/joomla/event/src/Dispatcher.php(454): Joomla\CMS\Plugin\CMSPlugin->Joomla\CMS\Plugin\{closure}()
#2 [ROOT]/libraries/src/User/User.php(803): Joomla\Event\Dispatcher->dispatch()
#3 [ROOT]/libraries/CBLib/CB/Database/Table/UserTable.php(628): Joomla\CMS\User\User->save()
#4 [ROOT]/libraries/CBLib/CB/Database/Table/UserTable.php(1119): CB\Database\Table\UserTable->store()
#5 [ROOT]/administrator/components/com_comprofiler/controller/controller.user.php(171): CB\Database\Table\UserTable->saveSafely()
#6 [ROOT]/administrator/components/com_comprofiler/admin.comprofiler.controller.php(289): CBController_user->saveUser()
#7 [ROOT]/administrator/components/com_comprofiler/comprofiler.php(14): require('/home/sabcorga/...')
#8 [ROOT]/libraries/src/Dispatcher/LegacyComponentDispatcher.php(71): require_once('/home/sabcorga/...')
#9 [ROOT]/libraries/src/Dispatcher/LegacyComponentDispatcher.php(73): Joomla\CMS\Dispatcher\LegacyComponentDispatcher::Joomla\CMS\Dispatcher\{closure}()
#10 [ROOT]/libraries/src/Component/ComponentHelper.php(361): Joomla\CMS\Dispatcher\LegacyComponentDispatcher->dispatch()
#11 [ROOT]/libraries/src/Application/AdministratorApplication.php(150): Joomla\CMS\Component\ComponentHelper::renderComponent()
#12 [ROOT]/libraries/src/Application/AdministratorApplication.php(195): Joomla\CMS\Application\AdministratorApplication->dispatch()
#13 [ROOT]/libraries/src/Application/CMSApplication.php(306): Joomla\CMS\Application\AdministratorApplication->doExecute()
#14 [ROOT]/administrator/includes/app.php(58): Joomla\CMS\Application\CMSApplication->execute()
#15 [ROOT]/administrator/index.php(32): require_once('/home/sabcorga/...')
#16 {main}
2024-09-03T05:01:08+00:00 CRITICAL 52.167.144.137 error Uncaught Throwable of type Joomla\CMS\Router\Exception\RouteNotFoundException thrown with message "Page not found". Stack trace: #0 [ROOT]/libraries/src/Application/SiteApplication.php(754): Joomla\CMS\Router\Router->parse()
#1 [ROOT]/libraries/src/Application/SiteApplication.php(244): Joomla\CMS\Application\SiteApplication->route()
#2 [ROOT]/libraries/src/Application/CMSApplication.php(306): Joomla\CMS\Application\SiteApplication->doExecute()
#3 [ROOT]/includes/app.php(58): Joomla\CMS\Application\CMSApplication->execute()
#4 [ROOT]/index.php(32): require_once('/home/sabcorga/...')
#5 {main}
2024-09-06T05:35:42+00:00 CRITICAL 1.146.176.23 error Uncaught Throwable of type Error thrown with message "Call to a member function assign() on null". Stack trace: #0 [ROOT]/libraries/src/Plugin/CMSPlugin.php(289): DigitalPeak\Plugin\User\DPCalendar\Extension\DPCalendar->onUserAfterSave()
#1 [ROOT]/libraries/vendor/joomla/event/src/Dispatcher.php(454): Joomla\CMS\Plugin\CMSPlugin->Joomla\CMS\Plugin\{closure}()
#2 [ROOT]/libraries/src/User/User.php(803): Joomla\Event\Dispatcher->dispatch()
#3 [ROOT]/libraries/CBLib/CB/Database/Table/UserTable.php(628): Joomla\CMS\User\User->save()
#4 [ROOT]/libraries/CBLib/CB/Database/Table/UserTable.php(1119): CB\Database\Table\UserTable->store()
#5 [ROOT]/administrator/components/com_comprofiler/controller/controller.user.php(171): CB\Database\Table\UserTable->saveSafely()
#6 [ROOT]/administrator/components/com_comprofiler/admin.comprofiler.controller.php(289): CBController_user->saveUser()
#7 [ROOT]/administrator/components/com_comprofiler/comprofiler.php(14): require('/home/sabcorga/...')
#8 [ROOT]/libraries/src/Dispatcher/LegacyComponentDispatcher.php(71): require_once('/home/sabcorga/...')
#9 [ROOT]/libraries/src/Dispatcher/LegacyComponentDispatcher.php(73): Joomla\CMS\Dispatcher\LegacyComponentDispatcher::Joomla\CMS\Dispatcher\{closure}()
#10 [ROOT]/libraries/src/Component/ComponentHelper.php(361): Joomla\CMS\Dispatcher\LegacyComponentDispatcher->dispatch()
#11 [ROOT]/libraries/src/Application/AdministratorApplication.php(150): Joomla\CMS\Component\ComponentHelper::renderComponent()
#12 [ROOT]/libraries/src/Application/AdministratorApplication.php(195): Joomla\CMS\Application\AdministratorApplication->dispatch()
#13 [ROOT]/libraries/src/Application/CMSApplication.php(306): Joomla\CMS\Application\AdministratorApplication->doExecute()
#14 [ROOT]/administrator/includes/app.php(58): Joomla\CMS\Application\CMSApplication->execute()
#15 [ROOT]/administrator/index.php(32): require_once('/home/sabcorga/...')
#16 {main}

Your issue is the same as BertusV. It's caused by DPCalendar. Unpublish its user plugin in System > Extensions > Plugins and that will resolve your issue.

That fixed the problem. Thank you very much for your guidance.

Cheers
Phil

Hi,
i had the same problem when i create a new user in joomla backend. Ther is a new release do not have permission to post links at this timeDPCalendar Development 9.2.0.11104 Release Candidate and at the moment i can not test it.
May be that release solve the problem.
greetings

now i have tested the release candidat and the problem is solved