If you get a pluggable.php file problem on your WordPress site, you may fix it by following the instructions listed below. The pluggable.php file problem might occur when you add a code snippet to your site or activate a new plugin. We’ll teach you how to solve pluggable.php file issues with WordPress in this post.
When and Why You See Pluggable.php Errors?
These functions will be found in the pluggable.php file if WordPress allows users and plugins to modify some fundamental functions. When a WordPress plugin or a custom code snippet fails to handle one of these methods appropriately, you’ll receive an error similar to this:
Warning: Cannot modify header information – headers already sent by (output started at /home/username/demosite/wp-content/themes/mytheme/functions.php:1035) in /home/username/demosite/wp-includes/pluggable.php on line 1179
Even if this or another mistake is still shown in the admin section, you may be allowed to continue working on your site. Let’s look at how to quickly resolve the pluggable.php file problem in WordPress.
Fixing Pluggable.php File Errors in WordPress
The file pluggable.php is a WordPress core file.
Even if there is an error pointing to them, it is not a good idea to change the core WordPress file as your first choice.
The mistake is most likely originating from a different location.
Simply look at the first address provided in the message to repair any mistake regarding the pluggable.php file.
Warning: Cannot modify header information – headers already sent by (output started at /home/username/demosite/wp-content/themes/mytheme/functions.php:1035) in /home/username/demosite/wp-includes/pluggable.php on line 1179
We can see an example of an error in the theme’s functions.php file at line 1035 in the example above.
That means you’ll need to modify the functions.php file in your theme and replace or delete the code that’s causing the problem.
In certain cases, the headers have already delivered an error due to an additional space after closing the php?> tag; simply remove that, and the problem will be resolved.
Let’s take a look at another example:
Warning: Cannot modify header information – headers already sent by (output started at /home/username/demosite/wp-content/plugins/some-plugin-name/some-plugin.php:144) in /home/username/demosite/wp-includes/pluggable.php on line 1090
This is the error message, and it indicates that the issue is caused by a plugin on your WordPress site.
Simply deactivate the plugin and tell the plugin’s creator of the problem.
Errors regarding the pluggable.php file are generally always not caused by the file itself.
A custom code snippet you contributed to the functions.php file, a badly designed plugin, or even your WordPress theme might cause these issues.
The problem can be resolved by simply deleting or modifying the code or disabling the plugin.
We hope that this post has been useful in resolving pluggable.php issues with WordPress.
