There are different status codes for Hyper Text Transfer Protocol (HTTPs), such as 1xx, 2xx, 3xx, and 4xx. Status codes help users understand – what happened to clients’ requests when dealing with server responses. Among status codes, the 5xx issues fall under Server errors.

In more detail, each letter in a status code shows specific information. For example, 501 errors indicate the server’s un-supported HTTP method for client requests, while 502 deals with invalid responses.

In this article – we are going to address 5xx issues in more detail. You’ll learn about 5xx issues, how to find and fix 5xx issues, and a brief explanation of 5xx error codes.

Introduction to 5xx errors

5xx errors occur when a server fails to handle users’ requests. In this case, a client’s request may exceed the server’s capabilities – triggering the 5xx errors.

5xx error statements explain what happened to the client’s request. For example, 501 Not Implemented, 502 Bad Gateway, and 503 Service Unavailable show different information about users’ HTTP requests.

5xx errors can also affect a site’s SEO. If a crawling Bot finds your site with a 503 error, search engines may drop your site from indexing.

Let’s learn about 5xx HTTP status codes and what they mean for a site owner, Support Team, or WordPress enthusiast.

5xx error codes

500 Internal Server Errors

The 500 errors occur when the origin of the malfunction is uncertain, happens in unexpected conditions, and is mostly – caused by mis-configured applications on a server.

501 Not Implemented

501 errors occur when a server fails to understand the client’s HTTP method. Also, a server may trigger 501 errors when a client’s request surpasses the server’s capabilities to process HTTP requests.

502 Bad Gateways

The 502 Bad Gateway status code is normal – and occurs when a server acts as a gateway or proxy. The 502 status code is triggered when a server receives an invalid response from another server.

503 Service Unavailable

As its name suggests, the 503 status code occurs when a server is temporarily unavailable. Such status codes show excessive overloads on a server or when a server is going through routine maintenance.

504 Gateway Timeout

In gateway or proxy servers, the 504 status code shows a delay in receiving a response from an upstream server. Simply put, when a proxy or gateway network server fails to respond within the given time frame, the 504 status code error occurs.

505 HTTP Version Not Supported

A server shows 505 HTTP Version Not Supported messages – when a client’s request initiates from an unsupported version of HTTP. You can see supported versions in the response and reasons why the client’s HTTP version is not supported.

506 Variant also Negotiates

A 506 error occurs due to a server mis-configuration – when dealing with negotiating part of content. In this case, a server detects a circular reference.

507 Insufficient Storage

As its name suggests, a server encounters 507 errors when it lacks enough memory to process a client’s request. In most cases, a 507 error is temporary on a server’s end.

508 Loop Detected

A server stops fulfilling the clients’ requests – if an infinite loop is detected. In this case, the entire operation is terminated by the server.

509 Bandwidth Limit Exceeded

A 509 error occurs when a client’s requests exceed a server’s bandwidth limits. In simple words, 509 errors indicate the failure of clients’ requests until bandwidth limits on a server are reset.

510 Not Extended

The 510 error occurs when a server asks for an extended client’s policy to process a specific request. In this scenario, a server also issues relevant instructions to the client.

511 Network Authentications Required

A server triggers 511 messages – when a client attempts to access a protected resource on the server. In this case, the client needs to authenticate the client before accessing the server resource.

How to detect 5xx issues?

You can find 5xx issues if checking each page’s server response is possible. Of course – the manual routines take time, consisting of checking the server’s HTTP responses for a status code. In manual ways – you’ll need to check server responses manually or by using a proxy, such as Burp Suite.

However, manual routines are not recommended – especially if your site has many pages. In this case, some automation plays well for site owners.

For example, an SEO Crawler helps you crawl your site’s pages, finds pages’ HTTP status codes, and lists codes under relevant categories – give a try to SEO Crawler.

Web admins can also use Google Search Console to find pages with 5xx status codes. In GSC, you can see a list of affected pages on the Crawl Errors page.

How to fix 5xx issues?

Sometimes – fixing 5xx issues is a matter of refreshing affected pages. Refreshing a page often fixes temporary errors, such as 500 and 503.

However, fixing complex server issues requires assistance from developers, server architectures, and subject matters. Also – you should have identified the status code before you can fix 5xx issues.

Here is a list of suggestions, procedures, and server configurations to help you fix 5xx issues.

• Check if a server is configured with correct file permissions on directories, scripts, and 3^rd party files. To get started – log into Hosting cPanel -> File Manager to see, change, and manage permissions on your site’s files.
• Source code formatting in the htaccess file can trigger 5xx issues. For example, mis-configured redirects in Htaccess can start 5xx issues on a WordPress site.
• See if CMS configuration files are correctly formatted with valid information, such as database credentials. For example, a single comma in WordPress wp-config.php file can trigger 5xx issues.
• Check if a server implements timeouts on specific processes. Here, you’ll need to ask for the Hosting representative’s support for more information.
• Make sure – a client’s infrastructure suits the requirements on the server. For example, make sure you’ve updated the client (browser) when dealing with the latest infrastructure on server. Such precautions help you avoid 505 HTTP Version Not Supported
• Exceeding PHP memory limits for script execution can also cause 5xx errors. To fix such issues, increase the memory allocation for script execution – ask your Hosting support representative.
• A server can return 5xx issues if a client requests a redirect chain. For example, if a page has multiple redirects, 5xx problems occur on a server.
• Exceeding hosting bandwidth limits also triggers 5xx issues on the server. With traffic at scale, big sites often need help with such problems. To fix such errors, site owners need to upgrade their hosting plans.
• Sometimes – accessing an authenticated resource on a server triggers 5xx issues. You can try logging in or attempting to access the page from a different IP address.
• Last but not least, for more information on 5xx origins – check your server’s log details. Each log can provide a status code ranging from 500 to 510.

Note: Only make changes if you know what you are changing at the server level. When a 5xx code error occurs and persists, you should consult a Hosting representative for assistance.

Over to you

5xx issues on a server occur – when processing clients’ requests goes wrong.

The origin of a 5xx error needs proper investigation, including dealing with configuration files, log details, timeouts, and 3^rd party scripts.

In this resource, you learned about 5xx errors and how to find and fix 5xx issues. If you need more information on 5xx errors’ SEO impacts, revising procedures, or one-time sessions, let us know we have a range of support plans for your WordPress website.