How to correct the warnings

Hello @satimis,

I hope you’re doing well.

Deprecated: Function has_cap was called with an argument that is deprecated since version 2.0.0! Usage of user levels is deprecated. Use capabilities instead.

It means the function has_cap is deprecated from the code or plugin. Currently, the logs are generating from the WordPress core; there is no theme or function mentioned.

First, you need to find which plugin, theme, or code is causing the issue because I can see the site has WP 6.8.1, which was released just 17 hours ago.

To find out what is responsible, you will need to create a site backup and start deactivating the plugins one by one, keeping track of the results. Do the same with the theme.

If the deprecated warning disappears after deactivating any plugin or theme, it confirms that it is coming from there.

You’ll need to try reinstalling a fresh version of the plugin or theme, which is going to help fix the deprecated warning. If you still get the deprecated warnings, then you need to contact the plugin or theme support and share this topic URL. They will understand and will remove the deprecated function from the code and release a new update.

Please try the test and share the outcome with us.

–
Kind Regards,
Imran Khan

The warnings you’re seeing on your WordPress website (https://lesousvide.com) are PHP errors related to deprecated functions and header issues caused by early output. Here’s how to fix them: 🔧 1. Fix the Deprecated Function Warning (has_cap)Error:

Deprecated: Function has_cap was called with an argument that is deprecated since version 2.0.0! Usage of user levels is deprecated.

✅ Solution:

This means that a plugin or theme is using an old method (user levels) instead of modern capabilities. This is usually safe to ignore unless you’re seeing actual functionality issues.

But to suppress the message:

• Edit wp-config.php (in your site root) and disable debug display:

define('WP_DEBUG', false); 
define('WP_DEBUG_DISPLAY', false);
@ini_set('display_errors', 0);

If you still want to log errors without showing them, you can add:

define('WP_DEBUG_LOG', true);

🛑 2. Fix “Cannot modify header information – headers already sent”Error:

Warning: Cannot modify header information – headers already sent by (output started at /path/to/functions.php:6121)

✅ Solution:

This happens because some output (like an error or space) was sent before PHP tried to modify headers (e.g., redirect or set cookies). Here’s how to fix it:

• Step 1: Ensure no whitespace or output before <?php or after ?> in any of these files:
  • /wp-includes/functions.php
  • /wp-includes/option.php
  • /wp-admin/admin-header.php

Ideally, there should be no ?> at the end of PHP files.

• Step 2: Fix the root cause — the deprecated warning.
  The warning itself counts as output, causing the headers error. By disabling the display of warnings (as above), the issue should disappear.

🧩 3. Track the Source Plugin Causing has_cap Warning

If you want to go deeper and fix the deprecated has_cap usage:

• Temporarily disable plugins one by one (starting with Wordfence or any custom plugins).
• Check which one causes the warning.
• If you’re a developer or have access to one, update that plugin to use modern capabilities instead of numeric user levels.

✅ Final Checklist Step Action 1 Edit wp-config.php to suppress errors from showing 2 Remove extra spaces before <?php and after ?> 3 Identify and update/remove outdated plugins or themes 4 Keep WordPress, themes, and plugins up to date

• This reply was modified 6 months, 1 week ago by Mahmoud Agwa.