500 Internal Server Error: What is it & How to Fix It

A 500 Internal Server Error is a general server-side error, meaning something has gone wrong on the website’s server, but the server isn’t able to provide specific details about the exact issue.

500 errors can also occur during the execution of server scripts or backend processes, making the execution stage a critical point where such issues may arise.

Large-scale monitoring data shows that 500 errors frequently appear among the top server-side failures. For instance, in a one-month snapshot, the monitoring platform Uptrends logged millions of 500-level errors—highlighting how prevalent and impactful they are.

Though 500 errors can appear in multiple forms, all of them point to server-side issues. Here are some examples of common variations:

• HTTP Error 500.31 — Failed to load ASP.NET Core runtime
• HTTP Error 500.19 — Internal Server Error, indicating a configuration issue on IIS
• HTTP Error 500.30 — ANCM In-Process Start Failure
• HTTP Error 500.21 — Internal Server Error (Module not supported)
• HTTP/1.1 500 — Generic Internal Server Error

Each error code can provide clues on the root cause, which we will discuss later.

From an SEO standpoint, these errors shouldn’t be ignored. As Google’s John Mueller explained, intermittent 500 errors aren’t an immediate cause for alarm—but persistent ones can lead Googlebot to crawl less and eventually drop URLs from its index. In fact, Mueller suggested that seeing more than 1% of requests resulting in 500 errors is a red flag that something is fundamentally broken.

When your website returns a 500 Internal Server Error, it affects your business in the following ways:

1. SEO Impact. Similar to 429 Error, Google and other search engines penalize websites with frequent server errors. A prolonged 500 status code can lead to lower rankings, as the site is deemed unreliable.
2. User Experience (UX). Users encountering a 500 error are left frustrated and confused, often abandoning the site. If users have the same problem multiple times, they are even more likely to leave your site.
3. Reputation. Regular server errors, such as 500 HTTP errors, make your site seem unstable. Over time, this can erode trust in your brand and push users towards competitors.

Unlike 4xx errors, which typically point to issues on the user’s side (such as a mistyped URL or invalid request), 5xx errors always indicate a problem on the server. In other words, the browser simply made a request, but the server couldn’t complete it.
Here are the most common technical causes of a 500 Internal Server Error, with notes on how to detect them.

• Corrupt or Misconfigured .htaccess File (Apache):

1. A single typo or unsupported directive in .htaccess can crash an Apache server.
2. How to check: Temporarily rename the file (e.g., to .htaccess_old) and reload the site. If it works, the error is in your configuration rules.

• Incorrect File or Directory Permissions

1. Web servers usually require specific permissions (e.g., 644 for files and 755 for directories). Too restrictive or too open settings can block execution.
2. How to check: Use SSH/FTP to verify permissions and correct them with chmod.

• Script Timeout or Memory Limits

1. Long-running scripts (PHP, Python, Node.js) can hit execution timeouts or exceed memory allocations. When this happens, the server halts execution and responds with a 500 error.
2. How to check: Review your server’s error logs (Apache error.log, Nginx error.log, or PHP error_log) for timeout or memory limit messages.

• Server Resource Overload

1. Spikes in traffic, database bottlenecks, or heavy background processes can exhaust CPU/RAM, leaving the server unable to respond.
2. How to check: Monitor resource usage with tools like top, htop, or hosting dashboards. Many providers offer built-in monitoring to spot overloads early.

• Faulty Plugins, Modules, or Updates

1. CMS platforms (WordPress, Drupal, etc.) may crash if a plugin update conflicts with the core system.
2. How to check: Disable recently added plugins/modules or roll back updates to see if the issue resolves.

Before attempting any fixes, it is important that the root cause is determined to ensure the correct troubleshooting steps are taken.

The above error can be triggered by a variety of issues, including corrupt files, permission problems, or connection failures.

Although 5xx errors are server-side by definition, sometimes what looks like a 500 error may actually stem from your local browser environment. Cached files or outdated cookies can cause your browser to display an error page even when the server itself is functioning normally.

• Cache stores copies of images, scripts, and stylesheets so pages load faster on repeat visits. If these cached assets are outdated or corrupted, the browser might fail to render the site properly.
• Cookies store session data (like login state, preferences, or shopping cart info). If they conflict with updated server-side settings, they can block requests or cause broken sessions.

Before assuming the issue is on the server, always clear cache and cookies to rule out local conflicts.

• Clear Cache. In your browser settings, go to Clear browsing data and select “Cached images and files.”
• Delete Cookies. In the same menu, choose “Cookies and other site data.” This will log you out of most sites but often resolves session-related issues.
• Use Developer Tools. Press F12 (Windows/Linux) or Option+Command+I (Mac) to open Developer Tools. Under the “Application” tab (Chrome) or “Storage” tab (Firefox), you can delete cache and cookies for a single website without affecting others.

If clearing cache and cookies fixes the issue, it was client-side. If the error persists, you’re likely facing a true server-side 500 error that requires further investigation.

One of the less obvious—but very common—causes of a 500 Internal Server Error is hitting the server’s memory ceiling. Every hosting environment allocates a fixed amount of RAM per process or script. When an application tries to consume more than this allocation, the server halts execution and responds with a 500 error.

In most cases, your error logs will include entries like:

This message clearly indicates a memory exhaustion issue.
How to fix memory-related 500 errors:

Increase the Memory Limit

• For PHP applications, update the php.ini file (e.g., memory_limit = 512M) or add a directive in .htaccess or wp-config.php (for WordPress).
• On Node.js or Python servers, review process managers (like PM2, Gunicorn) and container limits if running in Docker/Kubernetes.

Optimize Your Code and Plugins

• Inefficient loops, memory leaks, or poorly coded plugins/extensions can consume excessive resources.
• Audit your site’s codebase and disable or replace modules that cause spikes in memory usage.

Implement Caching

• Use object caching (e.g., Redis, Memcached) or page caching (Varnish, WordPress plugins) to reduce the load on your application and database.
• Proper caching ensures frequently requested content doesn’t require fresh computation every time, keeping memory usage stable.

Upgrade Hosting Resources (if needed)

• If your website traffic has grown significantly, the current hosting plan may simply be undersized. In such cases, scaling up your server resources (RAM/CPU) or moving to a VPS/cloud hosting solution can provide long-term stability.

To troubleshoot a 500 Internal Server Error, follow these systematic steps:

After completing these steps, refresh your site. If the error persists, it may require further investigation by your hosting provider.

Diagnosing and fixing HTTP errors like the 500 Internal Server Error becomes much easier with the right tools. Below are essential resources and methods to help you troubleshoot server issues:

How to Use These Tools Together
For instance, when a 500 Internal Server Error occurs:

1. Check server logs to identify the script or process that failed.
2. Use browser developer tools to confirm how the error appears to users.
3. Apply debugging plugins or code editors to trace and fix the root cause.
4. Reference online resources for guidance if the error persists.
5. Use monitoring tools to prevent or quickly detect future occurrences.

By combining these tools, you can efficiently diagnose, fix, and prevent 500 errors, ensuring your website remains accessible and reliable.

To reduce the likelihood of encountering 500 HTTP errors, follow these best practices:

Use try-catch blocks or equivalent mechanisms in your backend code to handle exceptions gracefully. For example, in PHP you can use set_error_handler() or frameworks like Laravel offer built-in error handling.

Track CPU, memory, and disk usage to prevent server overload. Tools like New Relic, Datadog, or UptimeRobot can alert you to spikes and performance issues.

Inefficient queries can slow down your server or cause timeouts. Use MySQL EXPLAIN or pgAdmin to analyze and optimize queries. Indexing frequently queried columns also improves performance.

Implement caching to reduce server load. Examples include Redis, Memcached, or CMS-specific plugins like W3 Total Cache for WordPress. Serving static content minimizes the risk of 500 errors during high traffic.

Regularly update server software, CMS platforms (like WordPress or Drupal), and plugins. Tools like ManageWP or InfiniteWP help automate updates and reduce vulnerabilities.

Check your website on multiple devices and browsers to ensure consistent performance. Services like BrowserStack or LambdaTest allow testing across a wide range of devices and configurations.

By applying these practices and using the right tools, you can significantly reduce the chances of encountering 500 Internal Server Errors and maintain a smooth experience for your users.

The 500 Internal Server Error is not the only server-side error you might encounter. Here are some related errors:

• 502 Bad Gateway. Indicates that one server acting as a gateway received an invalid response from an upstream server.
• 503 Service Unavailable. Typically occurs when the server is overloaded or undergoing maintenance.
• 504 Gateway Timeout. Occurs when a server acting as a gateway times out waiting for a response from another server.

If you encounter these errors frequently, it is recommended to contact your hosting provider's support for help in resolving the issue. Our team is also available to provide assistance with troubleshooting and fixing these server errors.

Each of these errors has different causes and solutions, but they share similarities with the 500 error in terms of impact and troubleshooting. If the problem persists, do not hesitate to seek further assistance.

Frequent 500 Internal Server Errors can severely affect user experience, damage your SEO rankings, and tarnish your brand’s reputation. By understanding the causes and solutions, you can reduce their impact.

However, if you find that server errors persist and your current provider isn’t resolving them promptly, it might be time to consider a change. Scalesta offers robust hosting solutions tailored for high-traffic websites, designed to prevent common server issues and ensure reliable performance.

Plus, we offer free migration services to make the switch smooth and stress-free. Let us keep your site running seamlessly! Contact us if you want to know more.

What is a 500 Internal Server Error?
It’s a generic server error indicating that something has gone wrong on the server, but the exact cause isn’t clear.

What causes HTTP Error 500?
Common causes include server overload, permission issues, and coding errors.

How can I fix HTTP 500 errors?
You can fix it by checking server logs, fixing file permissions, reviewing the .htaccess file, addressing coding bugs, or clearing your browser's cache to ensure you are seeing the most up-to-date version of your site.

How can I prevent future 500 Internal Server Errors?
Regular server maintenance, error handling in code, and server monitoring tools can help prevent 500 errors.

What’s the difference between a 500 error and a 504 error?
A 500 error is a generic server error, while a 504 error means a gateway server timed out while waiting for a response from another server.

Do I need to create an account to comment or interact with the site?
Yes, you need to create an account to comment or participate in discussions on our platform. Creating an account allows you to engage with other users and access additional features.

Why am I not seeing debugging information when troubleshooting a 500 error?
If the configuration setting for debugging is set to false, debugging information will not be displayed. Make sure to enable debugging in your configuration to view detailed error messages.