How to fix “Your website has a serious error” in WordPress

The main reasons and solutions of “serious errors in your website”
The key to understanding the serious errors in WordPress is to understand how WordPress uses the functions provided by its core files and combines them with the functions provided by the WordPress theme in use and all the activated plug-ins. If the code integrity is damaged, you will see a serious error on the WordPress website.

The following are the three main reasons behind the message “Your website has a serious error” in WordPress:

WordPress core, theme and plug-in failed to update.
Malware infection.
Server-side PHP problems and resource constraints.
1. WordPress core, theme and plug-in failed to update.
Failure to update or incomplete WordPress core, theme or plug-in update may lead to improper reinstallation of website files, which may lead to problems in PHP code execution. When your WordPress website fails to update, some of its files may be lost or damaged.

Once WordPress tries to load its core function and make your theme and activity plug-ins execute its code to extend this function, PHP will encounter a fatal error, which will lead to the message “There is a serious error in your website”.

How to solve
Depending on which component of your website causes serious errors in WordPress, you may need to reinstall WordPress core files, disable faulty plug-ins or switch to another theme. Unfortunately, because a serious error on the WordPress site will prevent you from accessing the WordPress administration area, all operations need to be performed from the command line or through the file manager interface of your virtual host control panel.

Replacing WordPress core files or correcting grammatical errors is a complex task. We strongly recommend that you save a backup of your website before changing any files to avoid more problems.

Replace WordPress core files
If you find a problem in the WordPress kernel, you will need to replace the damaged file or download the missing file again. You will need to download the WordPress installation version that failed to update the core functions of your website before, decompress the archive, and manually replace individual files or files in the entire wp-includes and wp-admin folder and the core WordPress installation directory.

Extended Reading: Getting Started with WordPress–Manually Updating WordPress Cores, Themes and Plugins

Switch to the default theme and disable the failed plug-in.
Because there is no way to access the WordPress management background, you need to download the theme you are currently using to the local computer through FTP or the online file management interface provided by the host company, and then delete the folder of the theme on the server, and make sure that the wp-content/themes directory contains at least one default theme that comes with WP. In this way, if the error is caused by the theme, we can log in normally by accessing your domain name /wp-admin/ at the WordPress background website.

If the error may be caused by the plug-in, we can rename the plugins folder to other names such as plugins123 in the wp-content directory, and then visit your domain name /wp-admin/ in the WordPress background website to log in normally.

It is strongly recommended to keep a default theme that comes with WordPress, so that the theme can be switched when it fails.

2. Malware infection
Malware infection is another reason to see serious errors in WordPress on your website. Just like the problems caused by failed update, any malicious code added to WordPress core, theme or plug-in file may lead to syntax errors or other problems that will destroy normal PHP code execution.

Hackers are always looking for new ways to exploit known vulnerabilities and visit your website to perform malicious operations and carry out network attacks. Your website file and its database information may be changed to such an extent that WordPress cannot run normally, which will lead to various errors, including the message “There is a serious error in your website”.

How to solve
This method is very similar to solving the failed WordPress update. Once the root cause of the problem is determined, whether it is the plug-in, the current theme or the core file that needs to be replaced, you need to restore the basic functions of WordPress to access the administrative area.

This kind of problem is more complicated, because we may not directly know what is infected with malicious software code, but we can only find the address core file, theme or plug-in, which is similar to the above. We need to download the latest WordPress file to replace it, switch to the default theme and disable the plug-in, and gradually find out, and there may be malicious code files in the upload directory wp-content/uploads. In short, such reasons can only be found by professionals. < br > It’s emphasized here: Never use themes or plug-ins from unknown sources, especially something that comes through unofficial sales channels of “free” or “reserve price”! ! !

3. Server-side PHP problems and resource constraints
Server-side problems and restrictions on the number of server resources available for WordPress websites may lead to various errors, including the message “Your website has a serious error”. How to configure and optimize your server environment for the specific needs of your website is the key.

Server-side problems related to PHP code execution errors may include the use of outdated PHP versions, which means that some new features may be completely unsupported or lack various PHP extensions required by WordPress. This also includes disabling certain PHP features that WordPress needs to disable.

PHP restriction
Server resource constraints can be a serious problem for WordPress website owners, especially in shared hosting plans where you have little control over the server environment. The limit on the amount of memory or CPU time that can be allocated to a specific PHP process may be very low, which usually leads to your WordPress website not working properly, especially if you have any resource-intensive plug-ins or custom code.

The three main PHP settings that significantly affect the function and performance of WordPress websites are:

PHP memory limit. The memory limit defines the maximum amount of memory that a PHP process can use.
Maximum execution time of PHP. The maximum execution time of PHP sets a time limit for executing each script. Once it is reached, the server will stop further script processing.
Maximum upload file size of PHP. The maximum upload file size determines the size of the file that can be uploaded to the server through a PHP script.
How to solve
Unless the shared hosting plan you use usually does not allow you to make any changes to the server environment, you can increase all PHP restrictions for all websites or specific websites, directories or even a single PHP script. You should also be able to switch to another PHP version.

Update PHP version
If the current version of PHP causes problems, it may happen when it no longer supports some new features required by your WordPress website, or when some extensions are missing, you can update it from your virtual host control panel.

Increase the global PHP limit
If you have a VPS or a dedicated server with a control panel, you can use the graphical user interface to manage all server-side aspects of PHP code execution through the graphical user interface. However, in most cases, you can only increase global restrictions in this way, which means that these restrictions will apply to all websites on the server.

This is not always the best solution, because we want to keep the restrictions as low as possible and increase the restrictions for some websites or scripts. You need to remember that, like any other server resource limitation, PHP limitation is to protect your server from overload or exploitation. Malicious scripts often use a lot of resources, so setting the PHP limit to the lowest value allowed by the website may be one of the factors to protect the system.

Increase PHP restrictions locally
You can increase the PHP limit of a specific website by creating user.ini file and placing new values in it. Each PHP handler has its own order when loading PHP configuration files, but user.ini usually has high priority, so all the configurations you include will take effect.

If you only want to increase the restrictions of a specific part of the website, please create a. user.ini file in the root directory or one of the directories where WordPress is installed. Insert a new PHP limit value as shown below and save the file.

Please note that the following values are for illustration purposes only, and you need to pay attention to the server resources available to you and set the limit considering all factors.
memory_limit = 256M;
max_execution_time = 120;
upload_max_filesize = 256M;
Check the new PHP configuration settings.
To check whether PHP has recognized the new values you configured, create a PHP information file, which will display all PHP configuration settings, including global values and values set specifically for your website. Create a file named phpinfo.php in the document root directory of your website and insert the following code into it:

Load the PHP information page by opening your domain name /phpinfo.php in the browser. You will see the new restrictions you have applied to your website under Local Values.

Fix WordPress’s Serious Errors in Three Steps
Please follow these three steps to solve all potential problems and restore your website by fully restoring WordPress functions.

Step 1. Enable debugging in WordPress.
When troubleshooting the message “Your website has a serious error” in WordPress, especially when your website is completely inaccessible, it is very important to check the website error log to understand the cause of the problem.

You can enable debugging mode in WordPress by setting the WP_DEBUG constant in the wp-config.php file to true. After refreshing the page, you can see the specific error message in the browser.

define( ‘WP_DEBUG’, true );
Step 2. Identify potential problems
After debugging is enabled in WordPress, please check the error message displayed on the website. This error message will help you identify the potential problem behind the message “Your website has a serious error” on the website.

Errors encountered by PHP will refer to WordPress core files, your active theme or one of the plug-ins. Check the log entries carefully to understand the type of problem you are dealing with. It may be a missing file or one of the PHP extensions, a syntax error, or you may notice that the PHP memory limit has been reached.

For example, if the PHP memory limit is reached and your WordPress website cannot be loaded, you will see a “serious error message on your website” error, and something similar to the following error will be recorded.

Step 3. Fix “Your website has a serious error”
Once the root cause of the problem is determined, you can solve the problems related to update failure, malware infection or server-side PHP problems according to the instructions provided in “Main causes and solutions of serious errors in your website”.

Restoring from the backup before the update failed may be the best and easiest way to get your website back online. If the recent backup must contain a working copy of your website, it is much easier to use the files in the backup than to re-download WordPress core files or manually remove malware.