Citrix Web Interface 5.2 and Presentation Server 4.0

We are currently in the process of migrating from Citrix Presentation Server 4.0 to XenApp 5.0 FP2, and have applications published from both farms.

I recently upgraded our Citrix Web Interface servers from version 5.11 to 5.2. It was a very simple, quick upgrade. However, after the upgrade, nobody could launch applications from servers running Presentation Server 4.0.

The problem ended up being that version 5.2 of the Web Interface does not support Program Neighborhood Agent/XenApp Plugin connections to 4.0 farms by default. I spent quite a while reading through the instructions, but missed that information somehow. There is one line in the WebInterface.conf file that has to be manually edited in order to enable connections to 4.0 farms:

To configure support for Presentation Server 4.0, Presentation Server 4.0 for UNIX, and XenApp 4.0 for UNIX

Updated: 2009-09-07

In this example, you want to configure a site for compatibility with Citrix Presentation Server 4.0, Citrix Presentation Server 4.0 for UNIX Operating Systems, and Citrix XenApp 4.0, with Feature Pack 1, for UNIX Operating Systems. New Web Interface sites are not initially compatible with these products—an additional manual site configuration step is required.

1. Using a text editor, open the WebInterface.conf file and locate the following line:

   RequireLaunchReference=On

2. Change the setting to Off, as follows:

   RequireLaunchReference=Off

   Note: Setting the RequireLaunchReference parameter to Off disables pass-through authentication to XenApp VM hosted apps. Users of this site will be required to enter their credentials each time they access a VM hosted app.

Here are some links to information on this issue:

Citrix support forum thread: http://forums.citrix.com/message.jspa?messageID=1410690
Citrix Web Interface 5.2 documentation: http://support.citrix.com/proddocs/index.jsp?topic=/web-interface-gransden/wi-server-requirements-gransden.html
Workaround for problem: http://support.citrix.com/proddocs/topic/web-interface-gransden/wi-configure-support-cps-4-gransden.html

I would like to know why Citrix didn't make this vital information more visible, instead of tucking it away in a tiny section of the server requirements section of their online documentation. It would have been nice if they included at least a warning, if not a option to enable 4.0 access, in the Web Interface 5.2 install wizard, rather than relying on the customer to manually edit the configuration file.