I'm upgrading from TYPO3 8.7 to TYPO3 9.5 and am getting the following error. I don't see anywhere in my site extension that that controller is used and don't know what do to. This error is preventing me from using any typo3cms commands. Looked for answers on the Slack channel and else where but haven't found answers yet and am stuck.

• Deleted all cache via the TYPO3 Install tool GUI
• Manually deleted and rebuilt vendor and typo3temp directories.

[ Symfony\Component\Console\Exception\RuntimeException ]                                     
  Command controller class "TYPO3\CMS\Lang\Command\LanguageCommandController" does not exist.  
                                                                                               

Exception code: 1520200175

Exception trace:
#0 ()
   vendor/helhum/typo3-console/Classes/Console/Mvc/Cli/CommandConfiguration.php:102
#1 Helhum\Typo3Console\Mvc\Cli\CommandConfiguration::extractCommandDefinitionsFromControllers()
   vendor/helhum/typo3-console/Classes/Console/Mvc/Cli/CommandConfiguration.php:94
#2 Helhum\Typo3Console\Mvc\Cli\CommandConfiguration::unifyCommandConfiguration()
   vendor/helhum/typo3-console/Classes/Console/Mvc/Cli/CommandConfiguration.php:149
#3 Helhum\Typo3Console\Mvc\Cli\CommandConfiguration->addCommandControllerCommands()
   vendor/helhum/typo3-console/Classes/Console/Mvc/Cli/CommandCollection.php:141
#4 Helhum\Typo3Console\Mvc\Cli\CommandCollection->addCommandControllerCommands()
   vendor/helhum/typo3-console/Classes/Console/Core/Kernel.php:138
#5 Helhum\Typo3Console\Core\Kernel->handle()
   vendor/helhum/typo3-console/Scripts/typo3-console.php:30
#6 {closure}()
   vendor/helhum/typo3-console/Scripts/typo3-console.php:32
#7 require()
   vendor/helhum/typo3-console/typo3cms:3

CodePudding user response：

Keep in mind, removed packages are also in your sysext-folder.

In your case, EXT:lang has been removed.

In my case, it has been relicts of typo3/cms while switching to a subtree-split installation of TYPO3.

Manually cleaning up your web-dir (and root-dir if used) by deleting your typo3/-folder will help.