A 500 Internal Server Error means something has broken on the server while trying to load your website — and instead of a normal page, your visitor sees an error message (sometimes a plain “500 Internal Server Error”, sometimes a white screen with a short error, sometimes “This site can’t be reached”). It’s frustrating because the message is deliberately vague: “server” doesn’t tell you what went wrong. The good news? On PBN LTD, 90% of 500 errors come from one of a small number of common, fixable causes — and you can sort almost all of them yourself from the dashboard. This guide walks you through exactly how, in plain English.

📑 What’s in this guide

🧠 What is a 500 Internal Server Error?

A 500 is the web’s way of saying “something failed on the server side — I can’t be more specific than that”. Unlike a 404 (file not found) or 403 (forbidden), a 500 doesn’t point at a specific problem. It’s a catch-all for any unexpected failure while the server was trying to build your page.

You might see it as any of these:

• “500 Internal Server Error” — the classic plain-text version.
• HTTP ERROR 500 — Chrome’s wording.
• “This page isn’t working” or “is currently unable to handle this request” — friendlier modern wording.
• A blank white screen — especially on WordPress (the famous “White Screen of Death”).
• “There has been a critical error on this website” — WordPress’s modern equivalent of the white screen.

The most common real causes on PBN LTD are:

🔍 60-second “what to check first” checklist

Before you change anything, run through these 6 questions. Most 500 errors are solved (or at least narrowed down) right here:

⚙️ WordPress sites — most common causes & fixes

On WordPress, the vast majority of 500 errors come from plugins, themes, or .htaccess. Work through these in order — the fix usually appears in the first one or two steps.

Step 1 — Try logging in to /wp-admin/ manually

If the One Click Admin Login button doesn’t work, that doesn’t always mean the WordPress admin itself is down. Try logging in manually first:

1. Visit https://yourdomain.com/wp-admin/ directly in your browser.
2. Log in with the WP Username and WP Password shown in your PBN LTD dashboard (click the site name → they’re in the overview).
3. If you get in — go to Step 2 (deactivate plugins from inside WordPress).
4. If you can’t reach /wp-admin/ either (500 there too) — go to Step 3 (work from File Manager).

Step 2 — Deactivate plugins from inside WordPress (if you can log in)

If you reached /wp-admin/:

1. Go to Plugins in the left-hand menu.
2. Tick the checkbox at the top to select all plugins.
3. Choose Deactivate from the bulk actions dropdown and click Apply.
4. Visit the front of your site. If the 500 is gone — reactivate plugins one at a time, refreshing the site after each one, until the 500 comes back. The last one you activated is the culprit.

Full walkthrough with screenshots: How to Resolve WordPress Plugin or Theme Conflicts.

Step 3 — Rename .htaccess via File Manager (the fastest catch-all fix)

A broken .htaccess is one of the single most common causes of WordPress 500 errors — especially after a plugin install, a redirect plugin edit, or a manual tweak. To rule it out:

1. Open File Manager (dashboard → site → Site Functions → File manager).
2. In the site root, find the file called .htaccess.
3. Rename it to .htaccess-backup (right-click → Rename). This temporarily disables the file.
4. Purge CDN cache (Site Functions → Purge CDN cache) and reload the site in an incognito window.

If your site comes back, the problem was your .htaccess. To regenerate a clean WordPress one:

1. Log in to /wp-admin/.
2. Go to Settings → Permalinks.
3. Don’t change anything — just click Save Changes. WordPress will automatically write a fresh, valid .htaccess file.
4. Now you can delete the old .htaccess-backup file (or keep it if you had custom rules you want to add back carefully — one at a time, testing after each).

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>
# END WordPress

Step 4 — Disable plugins via File Manager (if you can’t log in at all)

If /wp-admin/ also 500s, you can disable all plugins without logging in:

1. Open File Manager.
2. Navigate to /wp-content/.
3. Find the folder called plugins.
4. Right-click → Rename it to plugins-disabled.
5. Purge CDN cache and reload the site. If it works, a plugin was the cause.
6. Rename the folder back to plugins. Now log in to /wp-admin/ — you’ll see all plugins are deactivated. Reactivate one at a time to find the culprit.

Full walkthrough (including how to do the same with themes): How to Resolve WordPress Plugin or Theme Conflicts.

Step 5 — Check wp-config.php if you’ve edited it recently

If your 500 started immediately after editing wp-config.php (the file with your database details and config constants), the most likely culprit is a typo — a missing semicolon, a stray space before <?php, or an unclosed quote.

• Open wp-config.php in File Manager and undo your edit, or restore from a backup copy if you kept one.
• Make sure the very first line is <?php with nothing before it (no spaces, no blank lines, no “BOM” characters from some text editors).
• If you can’t recover it, restore a backup from the dashboard.

Step 6 — PHP memory limit (if you keep seeing 500s on specific pages)

If only certain pages 500 — especially heavy ones (e.g. WooCommerce admin pages, big plugin settings screens, the media library) — your site may be hitting the PHP memory limit. You can ask us to raise it on a support ticket (see below). Include the exact URL that 500s and roughly when it started.

🌐 Static HTML sites — most common causes & fixes

On a static HTML site there’s no PHP, no database, no plugins — so the list of things that can 500 is much shorter. It’s almost always one of three things.

1. A bad .htaccess file (by far the most common)

A single typo, a stray character, or an unsupported directive in .htaccess is enough to take a static site down with a 500.

For more on writing safe .htaccess redirect rules, see How to 301 Redirect (WordPress & Static HTML).

2. Missing or misnamed index.html

If your homepage file isn’t in the root, or it’s been renamed (e.g. Index.html with a capital I, or home.html), the server may return a 500 or a 403 instead of just a 404.

• Open File Manager and confirm there’s a file called index.html (all lowercase) in the root of your site.
• If your files are sitting inside a subfolder (e.g. /my-site/, /dist/, /public/), move everything up to the root.
• If the homepage file is called anything other than index.html, rename it. Filenames are case-sensitive — index.html and Index.html are different files to the server.

Detailed walkthrough: Fixing 404 Errors on Inner Pages (Static HTML Websites) — the same file-structure rules apply here.

3. Recently uploaded files (cache or upload corruption)

If the 500 started right after you uploaded files:

• Purge the CDN cache — cached 500s from before the upload can stick around for a while.
• If you uploaded a zip file, double-check it was extracted into the right place (and the zip itself isn’t sitting in the root).
• If an upload was interrupted, the file may be partially written. Re-upload from a fresh copy.

🧊 Don’t forget the cache

After any change in this guide:

1. Go to your PBN LTD dashboard → click the site → Site Functions dropdown → Purge CDN cache.
2. Open a fresh incognito / private window (your browser cache might be lying to you too).
3. Visit your site. Now you’ll see the real, current state.

💾 Last resort — restore a backup

If you’ve tried everything and the site is still throwing 500s, restoring a backup is often the fastest way back to a known-good state — especially for WordPress sites where the problem could be a corrupted database or a deeply broken plugin.

1. Open your PBN LTD dashboard and click on the affected site.
2. Look in the left-hand menu for “Site Details” / “Backups”.
3. Find the most recent backup from before the 500 started.
4. Click the Restore button (it looks like a play ▶️ icon).
5. Wait for the restore to complete, purge CDN cache, and test in incognito.

🧑‍💻 Still stuck? Submit a support ticket

If you’ve worked through this guide and the 500 still hasn’t shifted, open a support ticket. To get a fast, accurate answer, include:

• The exact domain name (and any specific URL that 500s).
• When the issue started (date and rough time, so we can match it against server logs).
• What you changed just before (new plugin, theme update, file edit, redirect rule, etc.).
• What steps you’ve already tried from this guide.
• A screenshot of the error message your visitors see.
• Confirmation you’ve purged the CDN cache and tested in incognito.

❓ FAQs

What does “500 Internal Server Error” actually mean?

It’s the server’s way of saying “I failed to build your page and I don’t have a more specific reason to give you”. On PBN LTD, it’s almost always something on the site side — a bad .htaccess rule, a plugin or theme conflict on WordPress, or files in the wrong place — rather than a hosting problem on our end.

Why is my whole site showing a white screen / “critical error”?

That’s WordPress’s version of a 500. It usually means a plugin, theme, or PHP error has crashed the site. Try logging in to /wp-admin/ manually (Step 1 above) — if you can, deactivate plugins from there. If you can’t, rename the plugins folder in File Manager (Step 4).

Do I need FTP or SSH to fix a 500 error on PBN LTD?

No. PBN LTD doesn’t offer FTP, SFTP or SSH and you don’t need any of them. Everything in this guide is done from the PBN LTD dashboard’s File Manager and/or your WordPress admin.

I deleted .htaccess — did I just break my site permanently?

No. For a static HTML site, you usually don’t need .htaccess at all (it only matters if you have redirects or other custom rules). For WordPress, just log in to /wp-admin/, go to Settings → Permalinks, and click Save Changes — WordPress will automatically write a fresh, valid .htaccess file for you.

Why does the 500 only happen on certain pages?

That usually points at a specific plugin, template file, or PHP memory limit. Heavy admin pages (WooCommerce, big plugin settings, media library) are often the first to hit memory limits. Open a support ticket with the exact URL and we can check / raise the limit if appropriate.

My site was fine yesterday and now shows a 500 — I haven’t changed anything!

Even if you didn’t change anything, sometimes plugins auto-update, themes get refreshed, or a recently-installed plugin only triggers an error under specific conditions. Run through the WordPress steps above — Step 3 (rename .htaccess) and Step 4 (rename the plugins folder) will rule out almost every cause in under a minute.

Can I see the actual PHP error message?

The detailed PHP error is logged on the server, not shown to visitors (a security best practice). If you’d like us to check the server logs for the exact error, include the time the 500 occurred (and the affected URL) when you submit a support ticket.

Should I edit WordPress core files to fix this?

No — never edit WordPress core files (anything in /wp-includes/ or /wp-admin/) to fix a 500. The fix is almost always in your .htaccess, your plugins, your theme, or wp-config.php. If you suspect the core files are corrupted, reinstall WordPress from your dashboard instead.

✅ Quick summary

• 500 Internal Server Error = something failed on the server side, no specific reason given.
• The #1 question: what did you change just before the 500 appeared? Undo it.
• For WordPress 500 errors: try /wp-admin/ manually, deactivate plugins, rename .htaccess, check wp-config.php.
• For Static HTML 500 errors: rename .htaccess, check for a valid index.html in the root, re-upload any corrupt files.
• Always purge the CDN cache and test in incognito after any change.
• Still stuck? Open a support ticket with the details above.