As the message implies, WordPress limits the types of files that you can upload to your site for security reasons. However, by adding a small code snippet to your site’s wp-config.php file or using a free plugin, you can manually expand the list of allowed file types so that you’re able to upload any type of file.
Edit the wp-config.php file, add the following code snippet above the /* That’s all, stop editing! Happy blogging. */ line:
Make sure to save your changes and re-upload the file if needed.