I was working on Fetching Publications from PubMedCentral into a WordPress Application using the plugin https://wordpress.org/plugins/pubmed-posts/
It worked like a champ on the Local Machine but when I uploaded it on the Hosting server running the CentOS platform it wouldn’t work. After debugging, I found php-xml (php dom extension) was not installed on the Hosting server.
To install it, run the command sudo yum install php-xml
and restart the service using command sudo service httpd restart