An error has occurred. 0 Joomla\CMS\Form\Form::getInstance() could not load file

[ribo]

Hello, when i am trying to create a new Shipment method it show me
An error has occurred.
0 Joomla\CMS\Form\Form::getInstance() could not load file
Joomla 4.3.1
vm 4.0.12

[jenkinhill]

Go to Joomla Global Configuration. Set "Error Reporting" as "Maximum" and enable the "Debugging" option.

Go to VirtueMart Configuration and set PHP Development mode for "all".

Now it should display the complete error trace and show you the exact file where the error is generated.

[ribo]

i put what you said and when i try to create shipmen method it show

An error has occurred.
0 Joomla\CMS\Form\Form::getInstance() could not load file
Call stack
#   Function   Location
1   ()   JROOT/libraries/src/Form/Form.php:1698
2   Joomla\CMS\Form\Form::getInstance()   JROOT/administrator/components/com_virtuemart/plugins/vmplugin.php:210
3   vmPlugin::getVarsToPushByXML()   JROOT/administrator/components/com_virtuemart/plugins/vmpsplugin.php:44
4   vmPSPlugin->getVarsToPush()   JROOT/plugins/vmshipment/weight_countriesstates/weight_countriesstates.php:26
5   plgVmShipmentWeight_countriesstates->__construct()   JROOT/libraries/src/Extension/ExtensionManagerTrait.php:242
6   Joomla\CMS\Application\CMSApplication->loadPluginFromFilesystem()   JROOT/libraries/src/Extension/ExtensionManagerTrait.php:160
7   Joomla\CMS\Application\CMSApplication->loadExtension()   JROOT/libraries/src/Extension/ExtensionManagerTrait.php:99
8   Joomla\CMS\Application\CMSApplication->bootPlugin()   JROOT/libraries/src/Plugin/PluginHelper.php:221
9   Joomla\CMS\Plugin\PluginHelper::import()   JROOT/libraries/src/Plugin/PluginHelper.php:181
10   Joomla\CMS\Plugin\PluginHelper::importPlugin()   JROOT/administrator/components/com_virtuemart/helpers/vdispatcher.php:89
11   vDispatcher::importVMPlugins()   JROOT/administrator/components/com_virtuemart/models/shipmentmethod.php:253
12   VirtueMartModelShipmentmethod->store()   JROOT/administrator/components/com_virtuemart/helpers/vmcontroller.php:173
13   VmController->save()   JROOT/administrator/components/com_virtuemart/controllers/shipmentmethod.php:56
14   VirtuemartControllerShipmentmethod->save()   JROOT/libraries/src/MVC/Controller/BaseController.php:678
15   Joomla\CMS\MVC\Controller\BaseController->execute()   JROOT/administrator/components/com_virtuemart/virtuemart.php:75
16   require_once()   JROOT/libraries/src/Dispatcher/LegacyComponentDispatcher.php:71
17   Joomla\CMS\Dispatcher\LegacyComponentDispatcher::Joomla\CMS\Dispatcher\{closure}()   JROOT/libraries/src/Dispatcher/LegacyComponentDispatcher.php:73
18   Joomla\CMS\Dispatcher\LegacyComponentDispatcher->dispatch()   JROOT/libraries/src/Component/ComponentHelper.php:361
19   Joomla\CMS\Component\ComponentHelper::renderComponent()   JROOT/libraries/src/Application/AdministratorApplication.php:143
20   Joomla\CMS\Application\AdministratorApplication->dispatch()   JROOT/libraries/src/Application/AdministratorApplication.php:186
21   Joomla\CMS\Application\AdministratorApplication->doExecute()   JROOT/libraries/src/Application/CMSApplication.php:293
22   Joomla\CMS\Application\CMSApplication->execute()   JROOT/administrator/includes/app.php:61
23   require_once()   JROOT/administrator/index.php:32

[ribo]

ok thank you.
i understood the problem.
It was a plugin not compatible. vmshipment
I  uninstall it and now it works

[jenkinhill]

Good.