Sometimes Scalar will just refresh the page when the Register or Sign In login links are clicked, preventing you from logging into your account or accessing any content currently on the site.
To fix this, first login into your account and go to cPanel. Click ‘File Manager.’
Navigate to the file system/application/config/config.php.
Find the line that reads
$config['uri_protocol'] = 'ORIG_PATH_INFO';
…and change it to
$config['uri_protocol'] = 'PATH_INFO';
Click ‘Save Changes.’
The site will come back online and you’ll be able to login to access the scalar dashboard now.