When trying to start an application from Web Interface the application fails to launch with the following error message:

"An error occurred while making the requested connection"

In addition the following error is seen in the Application Event Log:

Log Name: Application
Source: Citrix Web Interface
Event ID: 30107
Task Category: None
Level: Error
Keywords: Classic
User: N/A
Computer: server.domain.com
Description:
Site path: C:\inetpub\wwwroot\Citrix\XenApp.

The Citrix servers reported that they are too busy to provide access to the selected resource. This message was reported from the XML Service at address http://server.domain.com:80 [com.citrix.xml.NFuseProtocol.RequestAddress]. [Unique Log ID: 325a34c8]

The server the application is published on does not have a load evaluator assigned. This can be seen in QFARM:

C:\>qfarm /load

Server Name           Server Load
--------------------  ------------
SERVER                20000

From the Citrix Delivery Services Console:

- Right click on the server and select Other Tasks | Assign Load Evaluator from the context menu.

The load will go to 10000, then settle after a couple of minutes:

C:\>qfarm /load

Server Name           Server Load
--------------------  ------------
SERVER                10000

C:\>qfarm /load

Server Name           Server Load
--------------------  ------------
SERVER                200

Connections will now launch successfully.