If you are deploying Wyse Xenith zero clients to support a XenApp shared desktop infrastructure, you may run into a situation in which a locally attached USB printer is not mapped inside the XenApp session. I doubt this is real news to anyone as this may happen on any device, but the odd thing I witnessed last week is that I had, in this case, a Lexmark E250d attached to a Xenith zero client and when connecting to a XenApp session, not only did it not map, but there was no event log 1106 or 1107 “MetaFrameEvents” entry in the Application Log on the XenApp server. It was like the printer was not plugged in at all, though it was detected by the Wyse device itself.

One thing I did not know, is that the Xenith zero clients, do not support the Citrix Universal Print driver. I received the following from a Wyse engineer:

In the meantime you should realize that there is no support for the Universal Print driver on the Xenith. The only printing options through a Xenith/ThinOS device are by using a network printer, having printer drivers installed on the Citrix server or by using a 3rd party print utility such as ThinPrint which does support Wyse devices. In order for the Universal Print driver to work from Citrix, you would need to have a Windows OS installed on the local device.

Server 2008 R2 has a built-in driver for the Lexmark E250d called “Lexmark E250d (MS)”. However, even with these drivers installed, the printer was not mapped, and still, there were no Event Viewer logs/errors. The printer worked fine when attached to a computer or laptop.

Returning to the Xenith zero client, I tried enabling some additional options in the xen.ini file and added the following option to my “SessionConfig” line:

VUSB_PRINTER=Yes

But the problem persisted. I then opened Admin Mode on the device and looked at the printer settings, the defaults of which are shown below:

I was hoping for a “USB” printer option but there was none to be found, but while the port was LPT1, I clicked the Test Print button to see what would happen and to my surprise, a test page came out of the printer. Seeing that, I changed the print properties of the thin client to the following:

After making these changes, I logged back into my XenApp desktop and was able to print to the printer. Looking back at what I had done, I basically had changed:

a. The xen.ini to include the VUSB_Printer=Yes option
-I know that this change, by itself, did not result in any change

b. Set the Printer Identification variable on the print properties to match the driver installed on the XenApp server.

c. Enabled the printer on the print properties of the zero client.

I should have tested B and C individually to determine if one of these settings resulted in a successful print mapping but I didn’t. Should you run across this problem and test each option, let me know what you find.