A first-time user is a user who does not have Citrix Workspace app for Mac installed on their user device. Something as seemingly uncomplicated as a Citrix remote desktop not launching can be due to a number of causes. No OS changes to my knowledge on either Mac (and diff versions anyway). While you can still download older versions of Citrix Receiver, new features and enhancements will be released for Citrix Workspace app. Citrix Receiver Earlier Versions of Receiver for Mac Subscribe to RSS notifications of new downloads. Mark this reply as best answer, if it answered your question. Upvote if you found this answer helpful or interesting.