Attempting to launch Citrix XenApp / XenDesktop 7.x desktop or application published by NetScaler fails with the error: “The connection to “XenApp Desktop” failed with status (Unknown client error 1110).”

Problem

You attempt to launch a XenApp or XenDesktop published application or desktop published by NetScaler but receive the following error message:

The connection to “XenApp Desktop” failed with status (Unknown client error 1110).

Solution

One of the possible causes of this error message is if you have incorrect or have not configured any STA (Secure Ticket Authority) on your NetScalers.  Navigate to NetScaler Gateway > Virtual Servers, open the properties of the virtual server, scroll down to Published Applications and ensure STA Servers are configured: