For someone who has Error 500 on 1and1 shared host, there is a minimal changes on .htaccess. This is the modified .htaccess file.

<IfModule mod_rewrite.c>
    <IfModule mod_negotiation.c>
        Options -MultiViews
    </IfModule>

    RewriteEngine On

    ##
    ## You may need to uncomment the following line for some hosting environments,
    ## if you have installed to a subdirectory, enter the name here also.
    ##
    # RewriteBase /

    ##
    ## Black list protected files
    ##
    RewriteRule ^themes/.*/(layouts|pages|partials)/.*.htm /index.php [L,NC]
    RewriteRule ^uploads/protected/.* /index.php [L,NC]
    RewriteRule ^bootstrap/.* /index.php [L,NC]
    RewriteRule ^config/.* /index.php [L,NC]
    RewriteRule ^vendor/.* /index.php [L,NC]
    RewriteRule ^storage/cms/.* /index.php [L,NC]
    RewriteRule ^storage/logs/.* /index.php [L,NC]
    RewriteRule ^storage/temp/.* /index.php [L,NC]
    RewriteRule ^storage/framework/.* /index.php [L,NC]

    ##
    ## White listed folders and files
    ##
    RewriteCond %{REQUEST_FILENAME} -f
    RewriteCond %{REQUEST_URI} !\.js
    RewriteCond %{REQUEST_URI} !\.map
    RewriteCond %{REQUEST_URI} !\.ico
    RewriteCond %{REQUEST_URI} !\.jpg
    RewriteCond %{REQUEST_URI} !\.jpeg
    RewriteCond %{REQUEST_URI} !\.gif
    RewriteCond %{REQUEST_URI} !\.css
    RewriteCond %{REQUEST_URI} !\.less
    RewriteCond %{REQUEST_URI} !\.scss
    RewriteCond %{REQUEST_URI} !\.pdf
    RewriteCond %{REQUEST_URI} !\.png
    RewriteCond %{REQUEST_URI} !\.swf
    RewriteCond %{REQUEST_URI} !\.txt
    RewriteCond %{REQUEST_URI} !\.xml
    RewriteCond %{REQUEST_URI} !\.xls
    RewriteCond %{REQUEST_URI} !\.eot
    RewriteCond %{REQUEST_URI} !\.woff
    RewriteCond %{REQUEST_URI} !\.woff2
    RewriteCond %{REQUEST_URI} !\.ttf
    RewriteCond %{REQUEST_URI} !\.svg
    RewriteCond %{REQUEST_URI} !\.wmv
    RewriteCond %{REQUEST_URI} !\.avi
    RewriteCond %{REQUEST_URI} !\.mov
    RewriteCond %{REQUEST_URI} !\.mp4
    RewriteCond %{REQUEST_URI} !\.webm
    RewriteCond %{REQUEST_URI} !\.ogg
    RewriteCond %{REQUEST_URI} !docs/.*
    RewriteCond %{REQUEST_URI} !themes/.*
    RewriteRule ^ index.php [L,NC]

    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteRule ^ /index.php [L]
</IfModule>

The changes are in sentences index.php to /index.php. But not on the White listed folders and files part.

Thanks mate !

thanks a lot, this information never expires.

Thank you very much