A pluggable.php file error is something you may get when trying to add a code snippet on your website or activating a new plugin.
Here we will have a look at how you can fix pluggable.php file error in WordPress on the go.
What can cause a pluggable.php file error on your WordPress website?
This could be primarily because you are trying to override certain WordPress core functions. Undoubtedly, WordPress allows you to customize and override certain functions either manually or by using plugins.
However, at times, when the plugin or snippet code that you used is not able to handle the core functions of the WordPress, you are likely to get an error, something like this:
Warning: Cannot modify header information – headers already sent by (output started at /home/username/exampewebsite/wp-content/themes/mytheme/functions.php:134) in /home/username/examplewebsite/wp-includes/pluggable.php on line 1123
It is important to mention here that at times, you might still be able to work properly on the website while this error keeps popping up in the admin area.
How to fix this?
Pluggable.php file is one of the core files of WordPress and we would never recommend you editing that file even if the error keeps pointing to it.
In most cases, this error is actually coming from a different location, and in order to fix this error, it is essential to focus on the location mentioned.
In the example above, the error is pointing to the location in theme’s functions.php file at line 134.
This clears the confusion. You just need to head on to the theme’s functions.php file and change the line number 134 or fix it and see what is actually causing the error.
At times, it could be a simple extra space issue, or a missing php ?> tag.
Sometimes, a certain plugin might be the actual cause behind the error. In such cases, the error looks something like this:
Warning: Cannot modify header information – headers already sent by (output started at /home/username/exampewebsite/wp-content/plugins/pluginname/example-plugin.php:134) in /home/username/examplewebsite/wp-includes/pluggable.php on line 1123
It is easy to deduce that this error is pointing you to a plugin (example plugin in this case). To fix this, you may simply deactivate the respective plugin and see if that sorted out the error.
Pluggable.php file error is often not caused by the file itself, but by a poorly coded plugin or custom code snippet. In some cases, your theme could also be a culprit behind this problem.
Thus, the best way here is to check the code snippet or deactivate the plugin as the case might be.
If you have any questions or need help, you can always contact HostPapa Support by opening a support ticket. Details about how to open a support ticket are here.