I am using Multi-site Magento, where facing this issue for the Default store.
Except default store, the remaining stores and admin are working very well.
Homepage Error:
An error has happened during application run. See exception log for details.
Exception Log:
[] report.CRITICAL: InvalidArgumentException: Class does not exist in /usr/share/nginx/html/aveeva/vendor/magento/module-rule/Model/ConditionFactory.php:50
Stack trace:
#0 /usr/share/nginx/html/aveeva/vendor/magento/module-rule/Model/Condition/Combine.php(243): MagentoRuleModelConditionFactory->create('Amasty\Conditio...')
#1 /usr/share/nginx/html/aveeva/vendor/magento/module-rule/Model/AbstractModel.php(216): MagentoRuleModelConditionCombine->loadArray(Array)
#2 /usr/share/nginx/html/aveeva/vendor/magento/module-advanced-sales-rule/Model/Indexer/SalesRule/AbstractAction.php(97): MagentoRuleModelAbstractModel->getConditions()
#3 /usr/share/nginx/html/aveeva/vendor/magento/module-advanced-sales-rule/Model/Indexer/SalesRule/AbstractAction.php(71): MagentoAdvancedSalesRuleModelIndexerSalesRuleAbstractAction->saveFilters(Object(MagentoSalesRuleModelRuleInterceptor))
#4 /usr/share/nginx/html/aveeva/vendor/magento/module-advanced-sales-rule/Model/Indexer/SalesRule/Action/Full.php(63): MagentoAdvancedSalesRuleModelIndexerSalesRuleAbstractAction->reindex()
#5 /usr/share/nginx/html/aveeva/vendor/magento/module-advanced-sales-rule/Model/Indexer/SalesRule.php(54): MagentoAdvancedSalesRuleModelIndexerSalesRuleActionFull->execute()
#6 /usr/share/nginx/html/aveeva/vendor/magento/framework/Interception/Interceptor.php(58): MagentoAdvancedSalesRuleModelIndexerSalesRule->executeFull()
#7 /usr/share/nginx/html/aveeva/vendor/magento/framework/Interception/Interceptor.php(138): MagentoAdvancedSalesRuleModelIndexerSalesRuleInterceptor->___callParent('executeFull', Array)
#8 /usr/share/nginx/html/aveeva/vendor/magento/framework/Interception/Interceptor.php(153): MagentoAdvancedSalesRuleModelIndexerSalesRuleInterceptor->MagentoFrameworkInterception{closure}()
#9 /usr/share/nginx/html/aveeva/generated/code/Magento/AdvancedSalesRule/Model/Indexer/SalesRule/Interceptor.php(23): MagentoAdvancedSalesRuleModelIndexerSalesRuleInterceptor->___callPlugins('executeFull', Array, Array)
#10 /usr/share/nginx/html/aveeva/vendor/magento/module-indexer/Model/Indexer.php(455): MagentoAdvancedSalesRuleModelIndexerSalesRuleInterceptor->executeFull()
#11 /usr/share/nginx/html/aveeva/vendor/magento/module-indexer/Model/Indexer/DependencyDecorator.php(268): MagentoIndexerModelIndexer->reindexAll()
#12 /usr/share/nginx/html/aveeva/vendor/magento/module-indexer/Console/Command/IndexerReindexCommand.php(111): MagentoIndexerModelIndexerDependencyDecorator->reindexAll()
#13 /usr/share/nginx/html/aveeva/vendor/symfony/console/Command/Command.php(326): MagentoIndexerConsoleCommandIndexerReindexCommand->execute(Object(SymfonyComponentConsoleInputArgvInput), Object(SymfonyComponentConsoleOutputConsoleOutput))
#14 /usr/share/nginx/html/aveeva/vendor/magento/framework/Interception/Interceptor.php(58): SymfonyComponentConsoleCommandCommand->run(Object(SymfonyComponentConsoleInputArgvInput), Object(SymfonyComponentConsoleOutputConsoleOutput))
#15 /usr/share/nginx/html/aveeva/vendor/magento/framework/Interception/Interceptor.php(138): MagentoIndexerConsoleCommandIndexerReindexCommandInterceptor->___callParent('run', Array)
#16 /usr/share/nginx/html/aveeva/vendor/magento/framework/Interception/Interceptor.php(153): MagentoIndexerConsoleCommandIndexerReindexCommandInterceptor->MagentoFrameworkInterception{closure}(Object(SymfonyComponentConsoleInputArgvInput), Object(SymfonyComponentConsoleOutputConsoleOutput))
#17 /usr/share/nginx/html/aveeva/generated/code/Magento/Indexer/Console/Command/IndexerReindexCommand/Interceptor.php(23): MagentoIndexerConsoleCommandIndexerReindexCommandInterceptor->___callPlugins('run', Array, Array)
#18 /usr/share/nginx/html/aveeva/vendor/symfony/console/Application.php(1070): MagentoIndexerConsoleCommandIndexerReindexCommandInterceptor->run(Object(SymfonyComponentConsoleInputArgvInput), Object(SymfonyComponentConsoleOutputConsoleOutput))
#19 /usr/share/nginx/html/aveeva/vendor/symfony/console/Application.php(324): SymfonyComponentConsoleApplication->doRunCommand(Object(MagentoIndexerConsoleCommandIndexerReindexCommandInterceptor), Object(SymfonyComponentConsoleInputArgvInput), Object(SymfonyComponentConsoleOutputConsoleOutput))
#20 /usr/share/nginx/html/aveeva/vendor/magento/framework/Console/Cli.php(118): SymfonyComponentConsoleApplication->doRun(Object(SymfonyComponentConsoleInputArgvInput), Object(SymfonyComponentConsoleOutputConsoleOutput))
#21 /usr/share/nginx/html/aveeva/vendor/symfony/console/Application.php(175): MagentoFrameworkConsoleCli->doRun(Object(SymfonyComponentConsoleInputArgvInput), Object(SymfonyComponentConsoleOutputConsoleOutput))
#22 /usr/share/nginx/html/aveeva/bin/magento(23): SymfonyComponentConsoleApplication->run()
#23 {main} {"exception":"[object] (InvalidArgumentException(code: 0): Class does not exist at /usr/share/nginx/html/aveeva/vendor/magento/module-rule/Model/ConditionFactory.php:50)"} []