PHP - How to Troubleshoot 400 Errors

400 errors are typically caused by a permission setting in your PHP code. The most common are 400, 403, 404, and 429. If you experience one of these errors, you can use this article to troubleshoot and fix the issue.

Check Core Files

To begin, you will need to log in to your Bluehost Account Manager.

1. Once logged in, click the Hosting tab from the side navigation menu to the left.
2. Locate the website with the error you are troubleshooting, and click Settings.
3. Click the SECURITY tab from the horizontal menu.
4. Scroll down to the Check Core WordPress Files section, and click SCAN CORE FILES.

Check your website in a private or incognito browser window; if the error is still there, proceed to check permalink settings.

Check Permalinks

To begin, you will need to log in to your WordPress Admin Dashboard.

1. From the side menu to the left, click Settings.
2. From here, choose Permalinks.
3. Leave settings the same, and click Save Changes.

Check your website in a private or incognito browser window; if the error is still there proceed to temporarily disable the .htaccess file.

Disable .htaccess

To begin, you will need to log in to your Bluehost Account Manager.

1. Once logged in, click the Hosting tab from the side navigation menu to the left.
2. Locate the website with the error you are troubleshooting, and click Settings.
3. Click the ADVANCED tab from the horizontal menu.
4. From here, you will see an option for File Manager. Click MANAGE. This will open the folder your website's content is stored in.
5. Towards the top right corner, you will see a Settings option. Click here, check the box to Show Hidden Files (dotfiles), then Save changes.
6. Now that your dotfiles are showing, in the right section of the file manager, find the purple file icon named “.htaccess”. Right-click within that line, then, in the pop-up menu, choose Rename.

   Important: We want to rename the file instead of deleting it, as it may contain code that the website needs to function. Typically, we would rename to something like ".htaccess-old". Renaming your .htaccess file temporarily disables it.

7. Once disabled, you will need to generate a new .htaccess. Click the + File option in the top left corner.
8. In the pop-up box that appears, type .htaccess in New File Name. Double-check that the file is being created in the correct directory, then, click Create new file.
9. Once the file has been created, locate and Edit your new .htaccess.
10. Copy and paste the following code into your .htaccess file:
    # BEGIN WordPress 
     
    RewriteEngine On 
    RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}] 
    RewriteBase / 
    RewriteRule ^index\.php$ - [L] 
    RewriteCond %{REQUEST_FILENAME} !-f 
    RewriteCond %{REQUEST_FILENAME} !-d 
    RewriteRule . /index.php [L] 
     
    # END WordPress 
11. Click Save Changes towards the top right corner.

Check your website in a private or incognito browser window; if the error is still there, you may need to contact support to check your website and troubleshoot further.