Screen refresh issues with Citrix Receiver on Metaframe PS 4.0

Have you ever tried to connect to Citrix MPS 4.0 and XenApp 6.5 with the same client ? You could encounter this kind of problems.

For one of my customer, I’m in a migration process from Citrix MPS 4.0 to XenApp 6.5. As we publish applications, the process is to migrate one application at  a time. We plan to install a Web Interface to allow access to the old farm with recent online plugins (i.e receiver 3.4 and above). So, we’ve built 2 Web Interface sites (Web and service) on our Netscaler 10. This way, we expected that users could configure their Receiver to access both farms, during all the migration process. Unfortunately, tests revealed that user experience was ugly on MPS 4. Screen refresh took about 10sec to happen, and sometimes never happened.

We also tried to connect to the new Storefront 1.2 with our old online plugin (10.0). It worked untill we tried to connect to “stream to server” apps. We didn’t made more tests on it.

The facts

• receiver 3.3 and below : OK, everything runs fine.
• receiver 3.4, 4.0 & 4.0.1 : NOK, screen freezes.
• MacOS online plugin : OK, everything runs fine.

Debug

When your screen freezes, launch the “client connection status” windows to see traffic. On any action that have to change the screen (i.e open a new window), you see some incoming traffic but no screen update happens until you click on “reset” button in the connection status window. Hum… That’s looks like client side refresh problem.

The solution

There’s a new key in the receiver to correct this behavior. On x64 client, set it as follow :

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Citrix\ICA Client\Engine\Lockdown Profiles\All Regions\Lockdown\Virtual Channels\Seamless Windows]
"DeferredUpdateMode"="False"

On x86 client, set it as follow :

[HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\ICA Client\Engine\Lockdown Profiles\All Regions\Lockdown\Virtual Channels\Seamless Windows]
"DeferredUpdateMode"="False"

For multi-screen config, we also set the memory graphic to 8192 at farm level.

Sources : http://www.davethijssen.nl/2013/05/no-screen-updates-using-citrix-receiver.html