Applicable Products
Protocol driver error within a Citrix environment can mean so many things. But it comes down to this: the client cannot find the server. So if it were up to me, I'd change this message to 'The ICA client cannot connect to the XenApp server', or even sorter; Cannot connect to the Server.
- XenApp 6.5
- XenApp 6.0 for Windows Server 2008 R2
Symptoms or Error
When attempting to launch an application after changing the static IP address of the XenApp server hosting the application, the following error message appears:
“Unable to launch your application. Contact your help desk with the following information: Cannot connect to the Citrix XenApp server. Protocol Driver Error”
“Unable to launch your application. Contact your help desk with the following information: Cannot connect to the Citrix XenApp server. Protocol Driver Error”
Solution
To resolve the issue, complete the following procedure:- Stop the Citrix XTE Server service.
- Locate the httpd.conf file on the server.
- For 64-bit version of Windows Sever the file can be located by navigating to the “Program Files (x86)CitrixXTEconf” folder.
- For 32-bit version of Windows Server the file can be located by navigating to the “Program FilesCitrixXTEconf” folder.
- Open the file, httpd.conf, by using a simple text editor, such as Notepad.
- Locate any instance of an old IP address of the server and modify it to reflect the new IP address.
- Save the changes.
- Start the Citrix XTE Server service.
Problem Cause
When changing the static IP address of a server the applications fail to launch. One of the causes for this issue is that the httpd.conf file on the XenApp server is not updated with the new IP address of the server. The httpd.conf file is used by the Citrix XTE Server service for Session Reliability. If this file does not contain the correct information, applications fail to launch.
Additional Resources
CTX114680 – Event Log Error: An error occurred when processing incoming CGP downstream data