Problem:
Your WordPress installation running on Ubuntu 20.04 shows you this error message:
OTGS Installer, responsible for receiving automated updates for WPML and Toolset, requires the following PHP component(s) in order to function:cURL Learn more: Minimum WPML requirements
Solution:
You need to install the curl package for your PHP version.
Typically you can use
sudo apt -y install php7.4-curl
Doing this should immediately fix the issue (just reload your WordPress dashboard). In case you’re using PHP 7.2 you need to sudo apt -y install php7.2-curl instead.
In case the issue is still not fixed after doing this, try restarting your webserver (e.g. sudo service apache restart or sudo service nginx restart), try restarting PHP-FPM by using sudo service php7.4-fpm restart or sudo service php7.2-fpm restart or try rebooting your server. In case that doesn’t help either, you need to manually check which PHP instance the wordpress site is using and install the curl package for that PHP instance.