First, there's this blank page. A blank page with a few barely comprehensible instructions, in English. The number 503 appears here, and you also often see the following two words there: "service unavailable".
And then there's this feeling of distress, tinged with incomprehension. Suddenly, all at once, Your site has become unavailableJust like that, without warning. No doubt about it: you're facing a 503 error on WordPress.
To get rid of it as quickly as possible, follow our guide. In this article, you will discover the causes of this error, as well as 6 detailed, concrete solutions, with supporting screenshots, to fix it immediately.
If this does not solve the problem, please do not hesitate to contact our WordPress specialist agency.
What is a 503 error?
A 503 error indicates that your web hosting server cannot respond to a request made by a web browser. Therefore, the target page cannot be displayed, and the website you wish to browse is temporarily unavailable ("service unavailable").
If we take a moment to consider the technical aspects, you should know that...A 503 error is an HTTP error (on WordPress, we also find PHP, MySQL, and JavaScript errors).
About that, the Mozilla browser developer documentation indicates that the number 503 corresponds to "an HTTP server error response code".
That's the theory. In practice, A 503 error prevents you, the webmaster, from accessing the administration interface. (back office) of your WordPress site via the classic login page.
As you will see later in this article, you will need to use your FTP client to identify the source of the error and fix it.
What does a 503 error look like?
A 503 error can be quite confusing for you, because it gives almost no indication of the source of the problem.
Here is an example of a typical page that may appear on your screen when this error decides to cause you trouble:
In terms of clarity, we've seen better... And to top it all off, Note that this page can also be presented in different formats., with the display of error messages bearing the following labels, mostly in English:
- Error 503 Service Unavailable;
- 503 Error;
- Error 503: Backend Unavailable;
- 503 Service Unavailable;
- HTTP 503 Error or HTTP Error 503;
- HTTP Error 503;
- HTTP 503;
- HTTP status code: Error 503.
- HTTP Error 503: The Service is Unavailable.
- 503 Temporary Service Unavailable etc.
Why does this kind of unpleasant message suddenly appear, without you having requested it? Some answers are just below.
What are the main causes of a 503 error?
The Mozilla documentation, cited earlier in this article, provides a first concrete lead.
According to her, generally, a 503 error « This occurs because the server is down or inaccessible due to maintenance or overload..
You've made a little progress, but as you'll soon see, other factors can make your site temporarily unavailable. Let's break down the most important ones.
Cause #1 of error 503: Server overload
A 503 error message on your WordPress site may first appear on the screen when your hosting server is the victim of an overload.
In practical terms, this means that it is not able to handle an influx of visits during a traffic peak, especially if the server is shared (you share its resources and storage space with other webmasters).
An overload can also be caused by attacks from malwares (malware) or to bots (robots) that spam your site with the sole purpose of harming you.
Cause #2: Hosting server maintenance
After the overload, it's time for maintenance, which is the second cause of an HTTP 503 error.
To operate at full capacity, A web server needs to be maintained to function properly and remain secure.It is therefore sometimes updated, making your site unavailable.
Web hosting providers typically perform these types of operations overnight to minimize disruption to website availability. Some providers—though not all—will also notify you before any major maintenance is being deployed.
However, rest assured: these operations mostly happen without you realizing it.
Your server may also become temporarily unavailable when you update your WordPress site's plugins and themes.
In this case, the CMS (Content Management System) the most used across the planet enters what it calls a Maintenance Mode.
The following message may then appear on your screen:
Cause #3: A faulty extension or theme
If your WordPress plugins and theme are causing problems when you update them, They can also cause a 503 error on WordPress if they are poorly coded..
This occurs when they contain a PHP script that cannot be correctly interpreted by the server. Unable to display the requested message, the server becomes unavailable.
Similarly, you might also encounter a lovely 503 error when you decide to add a piece of custom code – in technical terms, this is called a snippet – on your WordPress site.
In the event of a syntax error or faulty code, your site may crash and the connection becomes impossible. No one will be able to access your services.
Tips Although less frequent than the first three, a faulty DNS configuration can also cause a 503 error. For your information, DNS stands for Domain Name System. It's a server that translates your domain name (e.g., maintenance-wp.fr) into an IP address. Wikipedia details.
As you can see, there are several reasons that can explain the presence of a 503 error. Although annoying, it can disappear automatically almost as quickly as it appeared.
If she continues to be glued to your screen, you'll have no choice. You'll have to roll up your sleeves and get rid of her.
For detailed instructions, go to the next section.
6 solutions to fix a 503 error on WordPress
#1 Reload the error page
You may have already experienced this. Sometimes, a very simple workaround can make a 503 error on WordPress disappear in a snap.
The recipe for the magic formula? A quick refresh of the unavailable page by refreshing it in your web browser.
For this purpose, Click on the F5 key on your keyboard, or on the "refresh" icon of your web browser:
With a bit of luck, your web server has gotten back on track in the meantime, and the page you want to view will be accessible again (its state is normal).
Feel free to repeat this operation for a few minutes to check that everything has returned to normal.
#2 Check your plugins to resolve a 503 error on WordPress
Refreshing your page doesn't fix the problem? Get to work. You're going to check that the source of the error isn't one of your extensions.
To begin with, there's a problem: you can no longer log in to your site from its visible interface (front-end), because no page can be displayed.
To access it, you have two options:
- use an FTP client (File Transfer Protocol). This is software that allows you to connect to your hosting server in order to manipulate the files and folders that make up your WordPress site;
- go through your hosting provider's admin panelFor your information, one of the most well-known is called cPanel. Many hosting providers use it, especially on shared servers.
In this article, we will opt for the use of FTP software, in this case FilezillaFree and open source, Filezilla is also one of the most popular tools, compatible on all platforms.
If it doesn't suit you, you can also turn to Cyberduck (macOS and Windows, free) or Transmit (macOS, paid).
Step 1: Connect to the FTP client
Install FileZilla on your computer, then Log in using the credentials provided by your hosting provider..
You will need to provide the following information:
- the host;
- the port;
- the username or identifier;
- the password.
Step 2: Create a new plugins folder
To understand this better, you should know that FileZilla is divided into two parts:
- on the left, you can access all the files and folders of your local site (your computer);
- On the right, you have the files and directories present on your remote site (the hosting server).
Head to the right-hand side, in public_htmlDepending on your hosting provider, this folder may have a different name, such as htdocs ou www.
For your information, this public_html is the root (root) of your site. Inside, you'll find all the directories and files of your website.
Double-click on the folder wp-contentThen rename the plugins folder inside, for example, to... plugins-erreur.
Continue by creating a new folder that you will name plugins (like the old one)WordPress will then automatically deactivate all your extensions.
Step 3: Try displaying your site
Now it's time to return to your browser to try displaying your site. You will face two options:
- The site is displaying againLog in using your WordPress credentials, then reactivate each plugin one by one, checking the display of your page each time.
Remove the plugin causing the HTTP 503 error from your FTP server, located in the wp-content > plugins folder. Once this is complete and all your plugins have been reactivated, remember to delete the folder.plugins-erreuron your FTP; - Error 503 is still thereIn this case, the problem must lie elsewhere, since your WordPress plugins do not appear to be the cause.
While waiting to proceed, delete the folderpluginson your FTP server and rename the folderplugins-erreurenplugins.
Tips To minimize problems with extensions, choose those listed on the official directoryTheir code is notably checked by a dedicated team before being added, which guarantees a certain level of quality. Also pay attention to the frequency of updatePay attention to user ratings and reviews. The better they are, the more likely you are to find a reputable extension. This advice also applies when choosing your theme.
#3 Check your theme
Your plugins aren't the problem? Don't despair, the 503 error might be coming from your theme.
The procedure is similar to that detailed in the previous subsection. In summary, you must:
- Access the wp-content > themes directory.
- Download your active theme folder by right-clicking and selecting "Download". Place it in a safe location on your computer, or even on an external hard drive.
- Delete the theme you just downloaded (right click > Delete).
In principle, WordPress will then automatically activate one of its default native themes.At the time of writing, the most recent native theme was called Twenty Twenty Two.
You might get a different theme at home, which will start with Twenty something.
Go back to your website and see if that darn 503 error is still there:
- she disappearedThat's great, your theme was probably the problem. Replace it with another one or, if you want to keep it, contact the theme's support to explain the issue;
- the error remainsReinstall your theme, the one you previously downloaded to your computer, by uploading it to your FTP server.
#4 Using WordPress Debugging
So far, you know that this 503 error on WordPress is not coming from your plugins or your theme.
The error might be due to a simple piece of PHP code. To try and find out, you can enable WordPress's "debug" mode.
To do this, activate a PHP constant called WP_DEBUGYou will find it in the file wp-config.php, which is located in the root directory of the site (in the folder public_html (for our example) on your FTP client.
In this file, Manually replace the value "false" with "true" on the line below:
define( 'WP_DEBUG', true );
define( 'WP_DEBUG_LOG', true );
Any errors related to PHP will appear in a log file named debug.log, accessible on your FTP via the following path: wp-content > debug.log.
Disclaimer This solution is more technical than the previous two, so skip it if you're not comfortable with the process. In fact, WordPress doesn't recommend using WP_DEBUG on a production site, but rather locally and on test sites.
#5 Optimize the database
Displaying errors via debug mode yielded no results? What if the root of the problem lies in your MySQL database?, which stores all the content of your site (plugins, themes, revisions, comments, settings etc).
The older your site gets, the more your database (DB) tends to grow by accumulating information, and the more likely it is to have difficulty functioning properly.
If it's not optimized, it can sometimes generate a 503 error. To address this, you can use a dedicated plugin. Some options include:
- WP-Optimize (free) ;
- Advanced Database Cleaner (freemium);
- WP Rocket (Premium). This caching plugin has a very handy tab for optimizing your database. Another interesting feature: it can also reduce Heartbeat API activitywhich can be responsible for a 503 error. By controlling heartbeat, you can save some server resources.
These extensions will help you do a nice clean-up, but first, contact your hosting provider, who may offer an option for this.
Regarding hosting providers, discover in the final subsection tips to improve the resources of the server they have assigned to you.
#6 Increase your server resources
Remember? A 503 error code is related to your server. Sometimes, it's also possible that the server no longer has sufficient resources to function properly.
Change your hosting plan to resolve a 503 error
If you are hosted on a shared server, it may no longer be powerful enough to absorb large increases in traffic, for example.
Contact your hosting provider to explain your problem. He might advise you to upgrade to a higher-level offer., more in line with your current needs.
Another option is to switch to dedicated web hosting (just for you), or WordPress-specific hosting. Performance will be better, but the price will also be higher than with shared hosting.
In any case, contacting your web hosting provider about your 503 error is always a good idea. Even if your hosting plan is still adequate, they might be able to help you identify the cause of the problem.
Increase the WordPress memory limit
If you are the stubborn type, Also try increasing the PHP memory allocated to WordPress, sometimes too weak with some hosting providers.
To do this, integrate the following code into the "wp-config.php" file:
define('WP_MEMORY_LIMIT', '512M');
Tips If you're using a Content Delivery Network (CDN) provided by your hosting provider (or a third-party solution), be wary of this service that promises to speed up page loading. It can sometimes cause 503 errors on your WordPress site! To be sure, disable it to check if this is happening on your end.
And if it's still blocked, what should I do?
Now you have a broad overview of error 503. Throughout these lines, you have discovered the major causes of this error, as well as step-by-step solutions to resolve it.
Since no one is immune to such an error occurring, we recommend that you frequently back up your site (files + database) to be better protected in case of a problem.
And if, after reading all our advice and our action plan, you are still unable to resolve this HTTP error, or do not feel comfortable taking action on your own, the WP Maintenance teams can assist you in resolving a 503.
Our WordPress support service will offer you a tailor-made solution that will meet your needs with speed, professionalism and efficiency.
