There's two different ways to implement Print & Delivery draft creation when working in Citrix environments.
This requires that Outlook client is installed in the citrix-server, outlook can either be used from the server or let the Outlook client synchronize the draft e-mails to the customers own system.
For an alternative you can use Exchange delivery method to shared inbox. This doesn’t require installation of outlook to the server. Only drawback is that you always need to use the shared inbox (only one account can be configured.)