Concept checklist (planned steps)

1. Connect to the webspace via FileZilla (FTP/FTPS/SFTP).

2. Locate the FlatPress installation folder (contains fp-content/, fp-interface/`, …).

3. Backup fp-content/config/settings.conf.php.

4. Edit settings.conf.php and set the theme back to leggero (optionally set a safe style).

5. Upload the changed file and verify permissions/transfer.

6. Optionally clear template/cache folders.

7. Reload the blog and confirm the 500 error is gone.

If a faulty theme was selected in the admin area, FlatPress may throw an HTTP 500 and you might not be able to access the backend anymore. In that case you can restore a working theme by editing the configuration file via FTP/SFTP.

* FileZilla installed

* Hosting access details:

• Hostname (e.g. ftp.yourdomain.tld)
• Username
• Password
• Port (21 for FTP/FTPS, 22 for SFTP – depends on your host)

* (Optional) Access to the hosting panel to confirm the correct web root folder (e.g. public_html/, httpdocs/)

* Open FileZilla.

* Go to File → Site Manager…

* Click New site and give it a name (e.g. “FlatPress Webspace”).

* Choose the protocol your host provides:

• SFTP – SSH File Transfer Protocol (recommended if available)
• or FTP with encryption enabled (often Explicit FTP over TLS / FTPS)

* Enter:

• Host
• Port
• User
• Password

* Click Connect.

* If FileZilla asks to trust a certificate/host key, verify it belongs to your host and accept it.

On the right side you see the Remote site.

Common web root folders are:

• public_html/
• httpdocs/
• htdocs/
• www/

How to recognize the correct FlatPress folder:

* Browse folders until you see these directories:

• fp-content/
• fp-interface/
• fp-includes/

* When you see them, you are in the FlatPress installation root.

* Navigate to: fp-content/config/

* Locate: settings.conf.php

* Download a backup to your PC:

• Right-click settings.conf.php → Download

* (Optional) Create a server-side backup if allowed:

• Copy the file and rename it to settings.conf.php.bak

* Right-click fp-content/config/settings.conf.php → View/Edit

* Your editor opens the file.

Look for the 'general' ⇒ array (…) section and find the theme entry, typically like:

'general' =>
  array (
    ...
    'theme' => 'CURRENT_THEME',
    'style' => 'CURRENT_STYLE',
    ...
  ),

Change only the theme value to leggero:

'theme' => 'leggero',

Optional (recommended for a “clean reset”): set a safe Leggero style, for example:

'style' => 'leggero-v2',

* Save the file in your editor.

* FileZilla will ask whether to upload the modified file back to the server → choose Yes.

Important: Don’t remove commas, quotes, or parentheses. A PHP syntax error in settings.conf.php can also cause a 500 error.

If the site still shows a 500 error, clear compiled templates so FlatPress rebuilds them.

* Open: fp-content/compile/

* Delete the contents (files) inside, but do not delete the folder itself.

Optional:

* Also clear: fp-content/cache/ (delete temporary files inside)

* Reload your blog in the browser (use a hard refresh if needed: Ctrl+F5 / Cmd+Shift+R).

* The site should load again using the Leggero theme.

* Theme folder missing: Check that fp-interface/themes/leggero/ exists on the server.

* A plugin is crashing: A broken plugin can also trigger 500. Check hosting error logs or temporarily disable plugins (advanced).

* Check the server error log: In many hosting panels you’ll find “Error Log” / “PHP error log” which shows the exact reason.