Printing to redirected LPT ports no longer works like expected from VDA version 2203 and above

[Rene Tap1709160993]

Hello Citrix engineers.

 

We have a strange problem and I hope that some can help us.

 

We use within a server VDI (VDA 2012) desktop a program in production that prints to a redirected lpt1 port on the client. We use the LPT and COM redirection that is applied via Citrix policies.

 

When we use VDA version 2203 or higher, that no longer works. If we print from the program, no print job is placed in the queue, but if we first give a print to lpt1 command via the command line    “dir > lpt1” inside the VDI it’s printed and then we can also print from the program.

 

Printing to a redirected LPT port works fine with the VDA versions 2012 (now live) and subsequent current releases up to 2112. From 2203 LTSR and above, printing to a redirected LPT port no longer works except when we issue the cli command “dir > lpt1” first.

 

Can you help us figure out this strange issue? Citrix support is also looking into it, but after several months now they haven’t found a solution yet.

 

The environment.

Windows 2019 server VDI (VDA 2012), non-persistent, vSphere and MCS images are created with Citrix Applayering

 

Kind regards,

René

[Rene Tap1709160993]

Problem solved. 

 

Disabling the policy "Virtual channel allow list" did the trick

 

“Starting with Citrix Virtual Apps and Desktops 7 2109, virtual channel allow lists are enabled by default.” – from https://docs.citrix.com/en-us/citrix-virtual-apps-desktops/policies/reference/ica-policy-settings/virtual-channel-allow-list-policy-settings.html

[Robert Young1709152714]

Hi Rene, 

Did you check it combined with the latest CWA  2203.1 CU3 ? https://www.citrix.com/downloads/workspace-app/betas-and-tech-previews/workspace-app-tp-for-windows-LTSR-cu21.html

I see a com port mapping issue fixed here that maybe also related to LPT port mapping. Worth a test.  "COM port redirection might be blocked during session roaming.  [CVADHELP-20959]"

This first appeared to us as COM port mapping failing after customers upgraded the VDA to 2203 but the final fix was on the CWA side in CU3.

 

I also see that the support case has now been moved to the next level. 

 

 

[Rene Tap1709160993]

Hi Robert,

 

Thanks, I'm going to install it.

 

 

 

[Rene Tap1709160993]

Hi Robert,

 

I've installed the CU3 version but the problem is still there.

 

Thanks,

René