Error: "Socket Operation on Non-Socket" and "Error 1030" When Launching Apps and Desktop Through NetScaler Gateway

1030 error when launching apps and desktop through NetScaler Gateway.

Error "Unable to launch your application. Contact your help desk with the following information: Cannot connect to the Citrix XenApp server. Socket operation on non-socket" when launching apps through NetScaler Gateway.

Complete the following steps to troubleshoot this issue:

1. Change the NetScaler Gateway setting from SmartAccess mode to Basic mode. For more information refer to CTX125567 - How to Configure NetScaler Gateway with Unlimited ICA Connections.
   
   Note: in latest 11.0 and 10.5 builds the SmartAccess mode and Basic mode options are replaced as below:
   
   SmartAccess mode is when "ICAOnly" checkbox is unchecked under Gateway vserver
   Basic mode is when "ICAOnly' checkbox is checked under Gateway vserver
   
   

2. Disable Session Reliability if it is enabled. This displays a different error message when connecting. Use this error message to troubleshoot this issue further.

3. If there are uncertainties about whether or not the firewall is blocking ports:

   1. ??Add a Service (load balancing service), for ports 1494 and 2598 and point to the XenApp server.

   2. Use protocol TCP.

   3. Verify to see which one (or both) fails.

   4. If it shows DOWN, then the port is being blocked between the NetScaler and the back end device.