Problema con la actualización de Prestashop

[Massimo333]

Intenté un par de veces actualizar mi versión de Prestashop 1.7.3.3 a la última versión (1.7.7) usando el complemento gratuito "Actualización con un clic", pero la actualización nunca tiene éxito y devuelve estos errores:

[INTERNAL] /home/u701403029/domains/maxpower.com/online/vendor/symfony/symfony/src/Symfony/Component/Config/Loader/FileLoader.php line 168 -
 Symfony\Component\Config\Exception\FileLoaderLoadException: Expected to find class "PrestaShopBundle\Controller\Admin\Configure\index" in file "/home/u701403029/domains/maxpower.com/online/src/PrestaShopBundle/Controller/Admin/Configure/index.php" while importing services from resource
 "/home/u701403029/domains/maxpower.com/online/app/../src/PrestaShopBundle/Controller/*", but it was not found! Check the namespace prefix used with the resource in /home/u701403029/domains/maxpower.com/online/app/config/config.yml (which is being imported from 
"/home/u701403029/domains/maxpower.com/online/app/config/config_prod.yml"). #0
 /home/u701403029/domains/maxpower.com/online/vendor/symfony/symfony/src/Symfony/Component/Config/Loader/FileLoader.php(90): Symfony\Component\Config\Loader\FileLoader->doImport('/home/u70140302...', NULL, false, '/home/u70140302...') #1
 /home/u701403029/domains/maxpower.com/online/vendor/symfony/symfony/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php(195): Symfony\Component\Config\Loader\FileLoader->import('config.yml', NULL, false, '/home/u70140302...') #2
 /home/u701403029/domains/maxpower.com/online/vendor/symfony/symfony/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php(127): Symfony\Component\DependencyInjection\Loader\YamlFileLoader->parseImports(Array, '/home/u70140302...') #3
 /home/u701403029/domains/maxpower.com/online/vendor/symfony/symfony/src/Symfony/Component/Config/Loader/DelegatingLoader.php(40): Symfony\Component\DependencyInjection\Loader\YamlFileLoader->load('/home/u70140302...', NULL) #4
 /home/u701403029/domains/maxpower.com/online/app/AppKernel.php(151): Symfony\Component\Config\Loader\DelegatingLoader->load('/home/u70140302...') #5 /home/u701403029/domains/maxpower.com/online/vendor/symfony/symfony/src/Symfony/Component/HttpKernel/Kernel.php(776): AppKernel->registerContainerConfiguration(Object(Symfony\Component\Config\Loader\DelegatingLoader)) #6
 /home/u701403029/domains/maxpower.com/online/vendor/symfony/symfony/src/Symfony/Component/HttpKernel/Kernel.php(642): Symfony\Component\HttpKernel\Kernel->buildContainer() #7
 /home/u701403029/domains/maxpower.com/online/vendor/symfony/symfony/src/Symfony/Component/HttpKernel/Kernel.php(135): Symfony\Component\HttpKernel\Kernel->initializeContainer() #8
 /home/u701403029/domains/maxpower.com/online/modules/autoupgrade/classes/UpgradeTools/SymfonyAdapter.php(74): Symfony\Component\HttpKernel\Kernel->boot() #9
 /home/u701403029/domains/maxpower.com/online/modules/autoupgrade/classes/UpgradeTools/CoreUpgrader/CoreUpgrader17.php(50): PrestaShop\Module\AutoUpgrade\UpgradeTools\SymfonyAdapter->initAppKernel() #10
 /home/u701403029/domains/maxpower.com/online/modules/autoupgrade/classes/UpgradeTools/CoreUpgrader/CoreUpgrader.php(86): PrestaShop\Module\AutoUpgrade\UpgradeTools\CoreUpgrader\CoreUpgrader17->initConstants() #11
 /home/u701403029/domains/maxpower.com/online/modules/autoupgrade/classes/TaskRunner/Upgrade/UpgradeDb.php(41): PrestaShop\Module\AutoUpgrade\UpgradeTools\CoreUpgrader\CoreUpgrader->doUpgrade() #12
 /home/u701403029/domains/maxpower.com/online/gestione7676/autoupgrade/ajax-upgradetab.php(53): PrestaShop\Module\AutoUpgrade\TaskRunner\Upgrade\UpgradeDb->run() #13 
{main}

¿Qué significan y cómo puedo solucionarlos?

[Luisejo]

Es algo que le está sucediendo a muchísimos usuarios.

A mi cada semana me entran 2 o 3 clientes nuevos con este fallo, y en la gran mayoría de casos, toca hacer tienda nueva y luego mover contenidos.
Pero en otros casos, el menor número, han podido avanzar pulsando de nuevo en actualizar tienda... eso si... arrastran errores en otras secciones.