The mystery of the Citrix Interceptor BHO

When there is a new fix or update released for a product I am working with frequently, I always like to read the release notes to see what has been fixed or what kind of new features has been added. This helps in calculating what kind of impact the fix\update will have when installing it in a environment. It frustrates me when there is new functionality added that is not listed in the release notes, and to make it worse when a production environment is suffering because of this.
This is exactly the case with the Internet Explorer Add-On from Citrix called the Citrix Interceptor BHO. (BHO = Browser Helper Object)

This Citrix Interceptor BHO is automatically added through one of the following ways :

– CtxVDAIEInterceptorBHO Class installed through Hotfix 025 for XenApp 6.5

– CtxIEInterceptorBHO Class installed through Citrix Receiver 3.2

When one of the above is installed, you will likely see popups  when opening Internet Explorer to allow this BHO and its components to load outside of Internet Explorer protected mode.
If you were lucky you spot this popup when going through a test procedure, but if Internet Explorer was not on your test list you will get a lot of calls to the support desk from frustrated users.
Imagine that your users (or worse some management staff) ask you what this Internet Explorer Add-on is about and you cannot really give a good answer to it, will they take you serious about the things you are installing in a production environment? I think this is really bad…

Neither the release notes of Citrix Receiver 3.2 or XenApp 6.5 Hotfix 025 has some details about this BHO, it looks like it’s kept top secret, the only information from Citrix I could find is the following :

“In recent releases of Citrix Receiver for Windows, Citrix has implemented a new Browser Helper Object (BHO) – CtxIEInterceptorBHO (IEInterceptor.dll). This BHO does not currently provide any additional functionality for the majority of customers running XenApp or XenDesktop and is actively used only by certain XenApp Cloud Service Provider customers.”

Ok so it’s not used for the majority of customers running XenApp or XenDesktop, only by certain XenApp Cloud Service Providers… Why is it (already) added to a public release of Receiver and a public release of a XenApp hotfix with so less information provided?

I think only Citrix can answer this question, my guess is that the BHO adds functionality for some reverse seamless\content redirection functionality from project Dorado and that Citrix will keep this secret till the functionality is officially announced (maybe with the release of XenApp 6.5 Rollup Pack 1)

Since there is so little information about this BHO, I now choose to disable this add-ons entirely till there is more information about it from Citrix. The BHO add-ons can easily be disabled through a group policy see this CTX KB for more details on how to do this.
In this way it’s easy to enable the add-on again when Citrix comes with more information about the BHO and you decide you want to use it.

In a previous blog I wrote a workaround to get rid of the annoying popup in IE and enable the BHO and its components for everybody, but for now I would advise to disable the Citrix BHO entirely till Citrix comes with more information about it.
If someone has additional information about the interceptor BHO please let me know.

Please note that the information in this blog is provided as is without warranty of any kind.