How to enable TWAIN Redirection for XenApp installed on Windows 2008 or Windows 2012

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By default starting with Windows 2008 Twain has been depreciated from the Windows operating systems which means the twain_32.dll XenApp users for its TWAIN redirection feature is not installed to "C:\Windows" directory. So when an application makes a call for twain_32.dll it is unable to find the file and in turn unable to find any scanners attached to the clients machine cause TWAIN redirection to fail.

This article explains??a few different ways to enable the TWAIN feature back into the Microsoft Windows operating system for use with XenApp.

To??enable TWAIN redirection you must install the Windows Desktop Experience feature.??You can add this feature through Microsoft Server Role Manager in both Windows 2008 and Windows 2012.



In Windows 2012 the feature is under a different location than in Windows 2008, it is located under:??User Interfaces and Infrastructure > Desktop Experience

Installing the Desktop Experience feature also requires the install of:

• Ink and Handwriting Services
• Media Foundation

Windows will prompt you to install these when you select the Desktop Experience feature for install.

After installing the Desktop Experience feature a restart of the XenApp server is required.??Once that has been completed TWAIN redirection in XenApp??will work as long as you have the corresponding XenApp policy to allow the feature.??It is a XenApp USER policy located under the Policies node in the Citrix AppCenter Console or the Citrix Delivery Services Console under section:??TWAIN Devices > Client TWAIN device redirection > (Set to Allowed)

Note: There is a work around If you do not wish to enable the Desktop Experience feature on your Windows servers you can manually enable TWAIN for XenApp by copying the twain_32.dll to the "C:\Windows" directory on each XenApp server.

The location of the twain_32.dll??is different for each Windows operating system are the following:

For Windows 2008 32bit

Copy twain_32.dll from:

C:\Windows\winsxs\x86_microsoft-windows-w..ion-twaincomponents_31bf3856ad364e35_6.0.6001.18000_none_893234485c30a

To:

C:\Windows

For Windows 2008 64bit

Copy twain_32.dll from:

C:\Windows\winsxs\x86_microsoft-windows-w..ion-twaincomponents_31bf3856ad364e35_6.0.6001.18000_none_893234485c30a

To:

C:\Windows

For Windows 2008 64bit R2

Copy twain_32.dll from:

C:\Windows\winsxs\x86_microsoft-windows-w..ion-twaincomponents_31bf3856ad364e35_6.1.7600.16385_none_89088a6bbd843

To:

C:\Windows

For Windows 2012 all versions

Copy twain_32.dll from:

C:\Windows\WinSxS\wow64_microsfot-windows-w..ion-twaincomponents_31bf3856ad364e35_6.29200.16384_none_ec508ff1a559dc0

To:

C:\Windows

Microsoft Documentation:

Deprecated Features for Windows 7 and Windows Server 2008 R2

http://technet.microsoft.com/en-us/library/ee681713(v=ws.10).aspx

Using scanners in Windows Server 2008 R2 with TWAIN drivers might require the installation of Desktop Experience Pack

http://technet.microsoft.com/en-us/library/ee940564(v=ws.10).aspx

Citrix Documentation:

If your application is not looking for twain_32.dll in (C:\windows) see the following article for a registry key from Microsoft to correct the applications behavior for Terminal Services and XenApp.

CTX107411 - How To Troubleshoot TWAIN Redirection Functionality with XenApp

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