XenApp Server Background Appears When an Application is Launched

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Article ID: CTX131818

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Updated On:

Description

When you launch an application, the XenApp Server background with the same size as the application Window that is opened is visible before the application Window appears as shown in the following screen shots.

User-added image

Environment

Caution! Using Registry Editor incorrectly can cause serious problems that might require you to reinstall your operating system. Citrix cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. Be sure to back up the registry before you edit it.

Resolution

One possible workaround to minimize the visibility of this issue is to disable the new logon user interface, forcing the server to use the old logon user interface, which uses a server side dialog box.

Caution! Refer to the Disclaimer at the end of this article before using Registry Editor.

To disable the new logon user interface you must make a registry change on the client workstation. Remove the VDTUI entry for the logon user interface from the list of VirtualDrivers, as highlighted in the following example:

For a Windows X32 Computer

[HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\ICA Client\Engine\Configuration\Advanced\Modules\ICA 3.0]
"VirtualDriver"="Thinwire3.0,ClientDrive,ClientPrinterQueue,ClientPrinterPort,Clipboard,ClientComm,ClientAudio,LicenseHandler,TWI,ZL_FONT,ZLC,SmartCard,Multimedia,ICACTL,SSPI,TwainRdr,UserExperience,VDTUI,DVCAdapter,GenericUSB,Flash"

For a Windows X64 Computer

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Citrix\ICA Client\Engine\Configuration\Advanced\Modules\ICA 3.0]
"VirtualDriver"="Thinwire3.0,ClientDrive,ClientPrinterQueue,ClientPrinterPort,Clipboard,ClientComm,ClientAudio,LicenseHandler,TWI,ZL_FONT,ZLC,SmartCard,Multimedia,ICACTL,SSPI,TwainRdr,UserExperience,VDTUI,DVCAdapter,GenericUSB,Flash,FlashV2”

Problem Cause

This issue occurs because of the way the Seamless technology is designed. This issue exists in the earlier versions of XenApp and Presentation Server, but only noticeable during a slow server response.
This issue is evident in XenApp 6 because of the new logon user interface used with the new Operating System Windows 2008 R2.

Issue/Introduction

When you launch an application, the XenApp Server background with the same size as the application Window that is opened is visible before the application Window appears.