5.1 Internal Server Error beim Aufrufen des Backends

Moin, ich habe mir für Testzwecke auf einem 1und1 Hosting die 5.1 installiert. Installations-Wizard lief einwandfrei durch und das Frontend läuft auch. Allerdings bekomme ich im Backend einen 500 Internal Server Error htaccess sieht wie folgt aus. was muss ich gegebenenfalls anpassen? Wenn ich #RewriteBase /shopware/ in RewriteBase / ändere dann läuft es weiter aber es kommt kein css. Wäre cool wenn jemand helfen könnte [quote]
RewriteEngine on

#RewriteBase /shopware/

Https config for the backend

#RewriteCond %{HTTPS} !=on
#RewriteRule backend/(.*) https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

RewriteRule shopware.dll shopware.php
RewriteRule files/documents/.* engine [NC,L]
RewriteRule backend/media/(.*) media/$1 [NC,L]

RewriteCond %{REQUEST_URI} !(/(engine|files|templates|themes|web)/)
RewriteCond %{REQUEST_URI} !(/media/(archive|banner|image|music|pdf|unknown|video)/)
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ shopware.php [PT,L,QSA]

Fix missing authorization-header on fast_cgi installations

RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization},L]

# Block access to VCS directories
RedirectMatch 404 /\.(svn|git|hg|bzr|cvs)(/|$)

# Restrict access to root folder files
RedirectMatch 404 /(composer\.(json|lock)|README\.md|UPGRADE\.md)$

# Staging environment #SetEnvIf Host “staging.test.shopware.in” SHOPWARE_ENV=staging # Development environment #SetEnvIf Host “dev.shopware.in” SHOPWARE_ENV=dev #SetEnv SHOPWARE_ENV dev DirectoryIndex index.html DirectoryIndex index.php DirectoryIndex shopware.php # Disables download of configuration
# Deny all requests from Apache 2.4+.

Require all denied

# Deny all requests from Apache 2.0-2.2.
<ifmodule>
    Deny from all
</ifmodule>

# Enable gzip compression
AddOutputFilterByType DEFLATE text/html text/xml text/plain text/css text/javascript application/javascript application/json


ExpiresActive on
ExpiresDefault “access plus 1 month”

<ifmodule mod_headers.c>
    Header append Cache-Control "public"
    Header unset ETag
</ifmodule>

FileETag None

# Match generated files like: # 1429684458_t22_s1.css # 1429684458_t22_s1.js

Header set Cache-Control “max-age=31536000, public”

<ifmodule mod_expires.c>
    ExpiresActive on
    ExpiresDefault "access plus 1 year"
</ifmodule>

# Disables auto directory index
Options -Indexes

Options -MultiViews

php_value memory_limit 256M

php_value max_execution_time 120

php_value upload_max_filesize 20M

php_flag phar.readonly off
php_flag magic_quotes_gpc off
php_flag session.auto_start off
php_flag suhosin.session.cryptua off
php_flag zend.ze1_compatibility_mode off
# AddType x-mapp-php5 .php # AddHandler x-mapp-php5 .php
Header append X-Frame-Options SAMEORIGIN
[/quote]

Gibt es eine aussagekräftige Fehlermeldung im Error-Log der Website oder in den Shopware-Logs?