An error has happened during application run. See exception log for details.
<br />
<b>Fatal error</b>:  Uncaught Exception: Warning: session_write_close(): Failed to write session data using user defined save handler. (session.save_path: /var/www/magento2/htdocs/var/session/) in /var/www/magento2/htdocs/vendor/magento/framework/Session/SessionManager.php on line 151 in /var/www/magento2/htdocs/vendor/magento/framework/App/ErrorHandler.php:61
Stack trace:
#0 [internal function]: Magento\Framework\App\ErrorHandler-&gt;handler(2, 'session_write_c...', '/var/www/magent...', 151, Array)
#1 /var/www/magento2/htdocs/vendor/magento/framework/Session/SessionManager.php(151): session_write_close()
#2 [internal function]: Magento\Framework\Session\SessionManager-&gt;writeClose()
#3 {main}
  thrown in <b>/var/www/magento2/htdocs/vendor/magento/framework/App/ErrorHandler.php</b> on line <b>61</b><br />