Cara mengatasi Server Error 500 Internal Server Error pada slims senayan yaitu :
1. Lihat file .htaccess pada folder slims, apakah ada atau tidak.
2. Jika ada, apakah isinya seperti dibawah ini ?

RewriteEngine on
# Apache/Senayan settings:
# by Hendro Wicaksono

# Protect files and directories from prying eyes.
<FilesMatch "\.(engine|att|inc|info|install|module|profile|test|po|sh|.*inc.php|.*sql|theme|tpl(\.php)?|xtmpl|svn-base)$|^(code-style\.pl|Entries.*|Repository|Root|Tag|Template|all-wcprops|entries|format)$">
  Order allow,deny
</FilesMatch>

# Don't show directory listings for URLs which map to a directory.
Options -Indexes

# Follow symbolic links in this directory.
Options +FollowSymLinks

# Force simple error message for requests for non-existent favicon.ico.
<Files favicon.ico>
  # There is no end quote below, for compatibility with Apache 1.3.
  ErrorDocument 404 "The requested file favicon.ico was not found.
</Files>

# Set the default handler.
DirectoryIndex index.php 
RewriteCond %{HTTP_HOST} ^katalog\.semaranglib\.web\.id$ [OR]
RewriteCond %{HTTP_HOST} ^www\.katalog\.semaranglib\.web\.id$
RewriteRule ^/?$ "http\:\/\/semaranglib\.web\.id\/katalog\/" [R=301,L]


# php -- BEGIN cPanel-generated handler, do not edit
# Set the “ea-php74” package as the default “PHP” programming language.
<IfModule mime_module>
  AddHandler application/x-httpd-ea-php74___lsphp .php .php7 .phtml
</IfModule>
# php -- END cPanel-generated handler, do not edit

3. Jika seperti diatas, hapus aja file .htaccess nya
4. Selesai
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