Body: <p>I just upgraded from Craft 2 to 3.6.14 (latest). I was able to successfully to the upgrade. I am able to get into the admin and was even able to install the feed-me plugin. I ported over all the files from the CraftCMS 2 to 3 (in a different folder) including the templates. When I try to hit the '/' URL (base URL), I get Internal Server Error with the following error.</p>
  <pre><code>2021-05-14 16:54:35 [-][1][a509bc948c7d5994a4c25b2437cf0413][error][TypeError] TypeError: Argument 1 passed to craft\web\twig\TemplateLoader::_resolveTemplate() must be of the type string, null given, called in /var/www/vendor/craftcms/cms/src/web/twig/TemplateLoader.php on line 72 and defined in /var/www/vendor/craftcms/cms/src/web/twig/TemplateLoader.php:108
  Stack trace:
  #0 /var/www/vendor/craftcms/cms/src/web/twig/TemplateLoader.php(72): craft\web\twig\TemplateLoader-&gt;_resolveTemplate(NULL)
  #1 /var/www/vendor/twig/twig/src/Environment.php(299): craft\web\twig\TemplateLoader-&gt;getCacheKey(NULL)
  #2 /var/www/vendor/twig/twig/src/Environment.php(381): Twig\Environment-&gt;getTemplateClass(NULL)
  #3 /var/www/vendor/craftcms/cms/src/web/twig/Environment.php(41): Twig\Environment-&gt;loadTemplate(NULL, NULL)
  #4 /var/www/vendor/twig/twig/src/Environment.php(513): craft\web\twig\Environment-&gt;loadTemplate(NULL)
  #5 /var/www/vendor/twig/twig/src/Template.php(317): Twig\Environment-&gt;resolveTemplate(Array)
  #6 /var/www/storage/runtime/compiled_templates/c7/c79cfef91787ef30e09834a18460ca59f19b243431dce3423759312bdef2fce8.php(38): Twig\Template-&gt;loadTemplate(Array, '', 1)
  #7 /var/www/vendor/twig/twig/src/Template.php(405): __TwigTemplate_31142054de6396a6abc4e01d6b275a8aef55865011e7064f16ec0f90eaa4b945-&gt;doDisplay(Array, Array)
  #8 /var/www/vendor/twig/twig/src/Template.php(378): Twig\Template-&gt;displayWithErrorHandling(Array, Array)
  #9 /var/www/vendor/twig/twig/src/Template.php(390): Twig\Template-&gt;display(Array)
  #10 /var/www/vendor/twig/twig/src/TemplateWrapper.php(45): Twig\Template-&gt;render(Array, Array)
  #11 /var/www/vendor/twig/twig/src/Environment.php(318): Twig\TemplateWrapper-&gt;render(Array)
  #12 /var/www/vendor/craftcms/cms/src/web/View.php(389): Twig\Environment-&gt;render('', Array)
  #13 /var/www/vendor/craftcms/cms/src/web/View.php(450): craft\web\View-&gt;renderTemplate('', Array)
  #14 /var/www/vendor/craftcms/cms/src/web/Controller.php(257): craft\web\View-&gt;renderPageTemplate('', Array, 'site')
  #15 /var/www/vendor/craftcms/cms/src/controllers/TemplatesController.php(100): craft\web\Controller-&gt;renderTemplate('', Array)
  #16 [internal function]: craft\controllers\TemplatesController-&gt;actionRender('', Array)
  #17 /var/www/vendor/yiisoft/yii2/base/InlineAction.php(57): call_user_func_array(Array, Array)
  #18 /var/www/vendor/yiisoft/yii2/base/Controller.php(181): yii\base\InlineAction-&gt;runWithParams(Array)
  #19 /var/www/vendor/craftcms/cms/src/web/Controller.php(190): yii\base\Controller-&gt;runAction('render', Array)
  #20 /var/www/vendor/yiisoft/yii2/base/Module.php(534): craft\web\Controller-&gt;runAction('render', Array)
  #21 /var/www/vendor/craftcms/cms/src/web/Application.php(278): yii\base\Module-&gt;runAction('templates/rende...', Array)
  #22 /var/www/vendor/yiisoft/yii2/web/Application.php(104): craft\web\Application-&gt;runAction('templates/rende...', Array)
  #23 /var/www/vendor/craftcms/cms/src/web/Application.php(263): yii\web\Application-&gt;handleRequest(Object(craft\web\Request))
  #24 /var/www/vendor/yiisoft/yii2/base/Application.php(392): craft\web\Application-&gt;handleRequest(Object(craft\web\Request))
  #25 /var/www/web/index.php(26): yii\base\Application-&gt;run()
  #26 {main}
  </code></pre>
  <p>I have tried to look for a solution pretty much everywhere. I have spent over 4 hours looking for a solution. I don't want to individually create entries in the new Craft 3 folder. Any suggestions or tips?</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2021-05-15T03:41:02.047Z
Comments.Text: When you upgraded to Craft 3, did you follow these instructions and start as if it was a Craft 3 site and then move everything over? https://craftcms.com/docs/3.x/upgrade.html#performing-the-upgrade Also, in which folder are your templates now?
Comments.UserDisplayName: CraftQuest
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2021-05-15T12:33:46.947Z
Comments.Text: @CraftQuest Yes. I followed the step-by-step instructions given in that link. The templates folder is the root folder of my project.
Comments.UserDisplayName: Karthik N G
Tags: <craft3><templating><craft2>
Title: Internal Server Error after upgrading from craftcms 2 to 3
ThreadText: # Internal Server Error after upgrading from craftcms 2 to 3
  
  (Asked by: username_0 on 2021-05-14)
  
  I just upgraded from Craft 2 to 3.6.14 (latest). I was able to successfully to the upgrade. I am able to get into the admin and was even able to install the feed-me plugin. I ported over all the files from the CraftCMS 2 to 3 (in a different folder) including the templates. When I try to hit the '/' URL (base URL), I get Internal Server Error with the following error.
  
  ```
  2021-05-14 16:54:35 [-][1][a509bc948c7d5994a4c25b2437cf0413][error][TypeError] TypeError: Argument 1 passed to craft\web\twig\TemplateLoader::_resolveTemplate() must be of the type string, null given, called in /var/www/vendor/craftcms/cms/src/web/twig/TemplateLoader.php on line 72 and defined in /var/www/vendor/craftcms/cms/src/web/twig/TemplateLoader.php:108
  Stack trace:
  #0 /var/www/vendor/craftcms/cms/src/web/twig/TemplateLoader.php(72): craft\web\twig\TemplateLoader->_resolveTemplate(NULL)
  #1 /var/www/vendor/twig/twig/src/Environment.php(299): craft\web\twig\TemplateLoader->getCacheKey(NULL)
  #2 /var/www/vendor/twig/twig/src/Environment.php(381): Twig\Environment->getTemplateClass(NULL)
  #3 /var/www/vendor/craftcms/cms/src/web/twig/Environment.php(41): Twig\Environment->loadTemplate(NULL, NULL)
  #4 /var/www/vendor/twig/twig/src/Environment.php(513): craft\web\twig\Environment->loadTemplate(NULL)
  #5 /var/www/vendor/twig/twig/src/Template.php(317): Twig\Environment->resolveTemplate(Array)
  #6 /var/www/storage/runtime/compiled_templates/c7/c79cfef91787ef30e09834a18460ca59f19b243431dce3423759312bdef2fce8.php(38): Twig\Template->loadTemplate(Array, '', 1)
  #7 /var/www/vendor/twig/twig/src/Template.php(405): __TwigTemplate_31142054de6396a6abc4e01d6b275a8aef55865011e7064f16ec0f90eaa4b945->doDisplay(Array, Array)
  #8 /var/www/vendor/twig/twig/src/Template.php(378): Twig\Template->displayWithErrorHandling(Array, Array)
  #9 /var/www/vendor/twig/twig/src/Template.php(390): Twig\Template->display(Array)
  #10 /var/www/vendor/twig/twig/src/TemplateWrapper.php(45): Twig\Template->render(Array, Array)
  #11 /var/www/vendor/twig/twig/src/Environment.php(318): Twig\TemplateWrapper->render(Array)
  #12 /var/www/vendor/craftcms/cms/src/web/View.php(389): Twig\Environment->render('', Array)
  #13 /var/www/vendor/craftcms/cms/src/web/View.php(450): craft\web\View->renderTemplate('', Array)
  #14 /var/www/vendor/craftcms/cms/src/web/Controller.php(257): craft\web\View->renderPageTemplate('', Array, 'site')
  #15 /var/www/vendor/craftcms/cms/src/controllers/TemplatesController.php(100): craft\web\Controller->renderTemplate('', Array)
  #16 [internal function]: craft\controllers\TemplatesController->actionRender('', Array)
  #17 /var/www/vendor/yiisoft/yii2/base/InlineAction.php(57): call_user_func_array(Array, Array)
  #18 /var/www/vendor/yiisoft/yii2/base/Controller.php(181): yii\base\InlineAction->runWithParams(Array)
  #19 /var/www/vendor/craftcms/cms/src/web/Controller.php(190): yii\base\Controller->runAction('render', Array)
  #20 /var/www/vendor/yiisoft/yii2/base/Module.php(534): craft\web\Controller->runAction('render', Array)
  #21 /var/www/vendor/craftcms/cms/src/web/Application.php(278): yii\base\Module->runAction('templates/rende...', Array)
  #22 /var/www/vendor/yiisoft/yii2/web/Application.php(104): craft\web\Application->runAction('templates/rende...', Array)
  #23 /var/www/vendor/craftcms/cms/src/web/Application.php(263): yii\web\Application->handleRequest(Object(craft\web\Request))
  #24 /var/www/vendor/yiisoft/yii2/base/Application.php(392): craft\web\Application->handleRequest(Object(craft\web\Request))
  #25 /var/www/web/index.php(26): yii\base\Application->run()
  #26 {main}
  
  ```
  
  I have tried to look for a solution pretty much everywhere. I have spent over 4 hours looking for a solution. I don't want to individually create entries in the new Craft 3 folder. Any suggestions or tips?
  
  **Tags:** craft3, templating, craft2
  
  > **Comments:**
  > **username_1**: When you upgraded to Craft 3, did you follow these instructions and start as if it was a Craft 3 site and then move everything over? https://craftcms.com/docs/3.x/upgrade.html#performing-the-upgrade Also, in which folder are your templates now?  
  > **username_0**: @username_1 Yes. I followed the step-by-step instructions given in that link. The templates folder is the root folder of my project.  
  
  ---
  
  ## 0 answers
  
  