A user is unable to start a Citrix XenApp Passthrough application and is presented with the following error from the Citrix Receiver:
Unable to launch your application. Contact your help desk with the following information: Cannot connect to the Citrix XenApp server. Protocol Driver error
CauseDue to new functionality of the Citrix Receiver it depends on TCP/IP + HTTP browsing. This has to be configured on the Managed Application.
Reconfigure the Managed Application to use TCP/IP + HTTP browsing.
- Open the Managed Application and go to the tab "Publishing"
- Open The Instant Passthrough settings by clicking on "Settings"
- Select "Use TCP/IP + HTTP browsing" and provide a name of a Citrix XenApp server and the XML port of this server
More information how to find the XML port: http://support.citrix.com/article/CTX128115/
It is also possible to configure this as a default on the Defaults tab in "Setup > Integration > Application Virtualization > Citrix XenApp Publishing" by editing "Settings".