To prevent this from happening we took the following steps: It is a sort hibernation mode for applications and causes the above described effect for users. The issue the users are experiencing seemed to be caused by a new feature in OSX 10.9 called App Nap. To clarify this issue I decided to write an article on how to fix unexpected disconnects with Citrix Receiver for Mac OSX. Beside the small note Dan Brinkman already wrote about this issue there is also a nice thread about the issue on the Citrix Discussions forum. While investigating the issue and some Googling by my colleague Patrick de Ritter we found that we where not alone. The users would receive the following message: When working on these devices their published applications would suddenly be disconnected. We were receiving complaints from several users that they would lose the connection to their published applications when working on their Mac OS X devices.