When trying to use a plugin in WordPress you receive something similar to the following error:
cURL error 28: Operation timed out after 5000 milliseconds with 0 bytes received
This could happen when refreshing or performing an action in the plugin.
This issue could be caused by multiple factors (Firewalls, PHP configuration, Outdated versions). However, one of the factors is due to allow_url_fopen being disabled:
To solve this issue, please read the following article on how to enable allow_url_fopen: Changing the "allow_url_fopen" Setting for PHP.