Hi Suman,
Thank you for your reply. I’m working on a new site, and your comment made me remember that this hosting provider, HostGator, does not default to the most recent version of PHP. Upgrading the PHP to 7.0 fixed the problem and HMWP is working perfectly now.
For the benefit of others who may stumble on this post, here’s what I did. If you are on HostGator, follow these instructions: (1) log into cPanel; (2) click on “PHP Selector” (located under Software); and (3) change the default PHP configuration for (at least) the public_html folder to 7.0 (or the most recent version you want to upgrade to).
To verify that you’ve successfully re-configured the PHP version, you can easily check the active version for your site by doing the following. In your HostGator cPanel, navigate to the “File Manager” (you can do this via FTP as well). In your public_html folder, create a file and title it “phpinfo.php”. Input the following code into the file:
<?php
phpinfo();
?>
To access this file, type http://example.com/phpinfo.php into your browser, replacing example.com with your site’s address. The page that loads will tell you which version of PHP your site is currently running. If you’ve done the above correctly re: PHP Selector, you should be good to go.
I apologize if I got anything wrong above. But hopefully this helps for anyone else experiencing this problem.
And, again, thanks Suman for your help.