Error: "Unable to launch your application. Contact your help desk with the following information: Cannot connect to the Citrix XenApp server. Network issues are preventing your connection. Please try again. If the problem persist, please call your help desk."

Here are a few things to check when you get a SSL 4 error. It may be one of the following and these are not in a certain order.

1. Make sure that the NetScaler Gateway certificate chain is complete on the NetScaler by linking it to its intermediate and root certificates. 
2. Make sure 1494 and 2598 shows "UP" when adding a LB Service on the NetScaler for backend XenApp application servers/VDA IPs.

• Verify if users can launch application inside the network. 
• If all works inside the network, save the .ica file and check the address field. 

3. If FQDN is used for XenApp, make sure the NetScaler can resolve it. If not, change this to use the IP address of the XenApp server (mostly for STA's). For more information refer to https://support.citrix.com/article/CTX128436
4. Verify that XenApp servers only have single NIC and no NIC teaming is used. 
5. Verify that routing from NetScaler to backend uses the same route.
6. Ensure that the license server is reachable to obtain the licenses.

Problem Cause