Craft 3 installation issue on account creation I try to install Craft 3 but I encounter an issue at the very beginning.
I uploaded the CMS via FTP and completed manually the .env file. When I try to run the installation, I get stuck at the account creation (the second step…) I want to create my account but the next button is doing nothing.
I get an error 400 "Bad Request // Unable to verify your data submission." When I send the form to create the admin account (POST to http://mywebsite.com/web/index.php?p=admin/actions/install/validate-account).

The server meet the requirements of Craft CMS (runned the server check and was ok). The DB connection is fine.

I tried to delete and reupload all the CMS but nothing changed.

Therefore, I'm unable to install Craft :| I saw some topics of the same issue but they're all unanswered.

Thanks a lot !

Here are the corresponding logs :

            2018-04-13 06:05:42 [2a02:a03f:3c1f:a00:6826:543f:275d:d8d5][-][-][error][yii\web\HttpException:400] yii\web\BadRequestHttpException: Unable to verify your data submission. in /home/MyWebsite/www/vendor/yiisoft/yii2/web/Controller.php:166
            Stack trace:
            #0 /home/MyWebsite/www/vendor/craftcms/cms/src/web/Controller.php(53): yii\web\Controller-&gt;beforeAction(Object(yii\base\InlineAction))
            #1 /home/MyWebsite/www/vendor/yiisoft/yii2/base/Controller.php(155): craft\web\Controller-&gt;beforeAction(Object(yii\base\InlineAction))
            #2 /home/MyWebsite/www/vendor/craftcms/cms/src/web/Controller.php(74): yii\base\Controller-&gt;runAction('validate-accoun...', Array)
            #3 /home/MyWebsite/www/vendor/yiisoft/yii2/base/Module.php(528): craft\web\Controller-&gt;runAction('validate-accoun...', Array)
            #4 /home/MyWebsite/www/vendor/craftcms/cms/src/web/Application.php(238): yii\base\Module-&gt;runAction('install/validat...', Array)
            #5 /home/MyWebsite/www/vendor/craftcms/cms/src/web/Application.php(446): craft\web\Application-&gt;runAction('install/validat...', Array)
            #6 /home/MyWebsite/www/vendor/craftcms/cms/src/web/Application.php(410): craft\web\Application-&gt;_processActionRequest(Object(craft\web\Request))
            #7 /home/MyWebsite/www/vendor/craftcms/cms/src/web/Application.php(147): craft\web\Application-&gt;_processInstallRequest(Object(craft\web\Request))
            #8 /home/MyWebsite/www/vendor/yiisoft/yii2/base/Application.php(386): craft\web\Application-&gt;handleRequest(Object(craft\web\Request))
            #9 /home/MyWebsite/www/web/index.php(21): yii\base\Application-&gt;run()
            #10 {main}
Hello and thanks Brad !

I was actually using Firefox. When I tried to install Craft 3 via Chrome (which has never gone to the website before) the issue was solved and I could access to the next page. Should be a cache issue !

Thank you !

Olivier.