Chrome: Citrix Receiver Plugin Unsupported

A recent issue was brought to our attention by a client when a message appeared in the Chrome browser, stating that the Citrix Receiver plugin was not supported. I will walk you through the solution in this week’s post.

While accessing a Citrix StoreFront or Web Interface site in Google Chrome, you may see something like this:

This does not mean that Citrix will no longer support the Receiver. This is actually an issue with the Chrome browser. In order to improve security, Google has decided to disable NPAPI plugin support in the Chrome browser. This affects both Windows and Mac installations. This means that those Chrome plugins we have grown to love and count on will no longer work by default. “By default” is the operative statement here and I will get back to that.
Updates of Chrome as of April 2015 remove NPAPI support. This results of this change have already appeared for the Citrix Receiver. The Receiver Plugin is what checks to see if we already have a client installed and whether it is up to date. It is then responsible for launching applications/desktops when we click on the icon. The plugin is no longer running, so StoreFront will always ask you to install the receiver because it cannot tell if you have it:

This will also affect NetScaler implementations:

The next thing that will happen is you will not be able to launch an application by just clicking a presented icon. Instead, it will ask to be saved:
And you will have to click on the saved .ICA file to launch the application:
Annoying, isn’t it. So, how do we get around this?

  1. Upgrade to the latest and greatest. Unfortunately, the upgrade is not only on the client side. Citrix has just released updated versions of the Receiver (Windows Receiver ver. 4.3 and Mac Receiver ver. 12.0) and for StoreFront (ver. 3.0). The combination of the latest StoreFront and Receiver will work around this issue with Google Chrome and a similar issue with Microsoft Edge. I believe HTML 5 is used instead of a plugin, but I need to confirm that.
  2. Re-enable NPAPI support. (Note: This is opening up the security holes Google is trying to close. Do this at your own risk.) NPAPI support is disabled by default. We can change the default. Here is how:
    • In Chrome’s address bar, type “chrome://flags/#enable-npapi”:
    • In the list that appears, find “Enable NPAPI Mac, Windows” and click Enable:
    • Click the “Relaunch Now” button on the bottom of the screen. It appears after you make your changes:
    • After relaunch, you will probably still see the warning about the plugin being unsupported because that is part of Chrome. There is probably some way to get rid of it by modifying Chrome, but I am not getting into that here.

There you have it. I hope this helps. If you have any questions or comments, please feel free to leave them in the space below.You can also reach me directly by email.





Craig R. Kalty (CCIA, CCEE, CCA, MCITP:EA, MCITP:SA, VCP)| Sr. Network Consultant



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