How to Fix the “Upload: Failed to Write File to Disk”

The “Upload: Failed to Write File to Disk” error occurs when WordPress encounters issues while trying to save uploaded files to the server. This could be due to incorrect folder permissions, inadequate server space, or conflicting settings.

Steps to Resolve the Error:

1. Check Folder Permissions:

Incorrect folder permissions can prevent WordPress from writing files to the server. Besides, access your hosting account via FTP or a file manager. Also, ensure that the wp-content/uploads directory has the correct permissions (usually 755 or 775).

2. Adjust PHP Settings:

Sometimes, PHP settings might limit the size of uploaded files or the memory available for processing. Firstly, access your php.ini file. Otherwise, use a plugin like WP Memory Usage to adjust settings related to upload_max_filesize, post_max_size, and memory_limit.

Example of php.ini settings:

upload_max_filesize = 64M
post_max_size = 64M
memory_limit = 128M

3. Check Available Server Space:

Insufficient disk space on your server can cause upload failures. So, contact your hosting provider to ensure you have enough space available.

4. Verify Temporary Folder Location:

WordPress uses a temporary folder to store files during upload. So, ensure this folder exists and has proper permissions. Also, you can define or modify it in your wp-config.php file:

define('WP_TEMP_DIR', '/path/to/temp/folder');

5. Disable Plugins/Themes:

Conflicting plugins or themes might cause this error. Temporarily deactivate all plugins and switch to a default WordPress theme (like Twenty Twenty-One) to check if the issue persists.

6. Debug WordPress:

Enable WordPress debug mode to identify any specific error messages. Add the following lines to your wp-config.php file:

define( 'WP_DEBUG', true );
define( 'WP_DEBUG_LOG', true );
define( 'WP_DEBUG_DISPLAY', false );

7. Modify .htaccess File:

In some cases, incorrect rules in the .htaccess file can lead to upload failures. Make a backup and then try replacing the existing .htaccess file with a default WordPress .htaccess file.

8. Contact Hosting Support:

If none of the above steps resolve the issue, reach out to your hosting provider’s support team. They might have insights or server-level configurations causing the problem.

Resolving the “Upload: Failed to Write File to Disk” error involves checking various aspects like folder permissions, PHP settings, available server space, and potential conflicts within WordPress itself.