Some email hosting, web hosting, or APIs require IP addresses to be whitelisted when making a connection to the server for security reasons. This means that some features in Workflow Automations will not work unless all Workflow Automations servers are whitelisted beforehand.
Features that may be affected are: Send and Email, Remote POST/GET, MySQL Sync.
If these or other applications cannot establish a connection, contact your technical support team and ask if IP addresses will need to be whitelisted.