FWIW, webex app.msi version 39.9.2.116 includes two DLLs: ptolkadd.dll and ptolkadd64.dll which both show as version 3905.0.1905.800
With this version of webex app.msi, the Preferences UI includes an additional section called Integrations that looks like this:
And the Calendar section looks like this:
This 39.9.2.116 version with this Outlook Add-In works fine for my corporate Office 365 Enterprise Outlook.
Newer versions of the webex app.msi do not include these Outlook Add-In DLLs and Webex Outlook integration does not work for me. I have tried webexapp.msi versions 40.8.2.17, 39.11.2.4 among others which I have confirmed do not include the Outlook integration DLLs mentioned above.
With newer versions of webexapp.msi, the Integrations section is missing and the Calendar section looks like this:
Or this:
At one point I tried copying in the Outlook Add-In DLLs I saved from a 39.9.2.116 version into the appropriate Webex installation folder which may be why I captured two different views for Preferences > Calendar. It did not result in Outlook integration working. Using Outlook to manually select the appropriate DLL for the Outlook Add-In also failed - no error message, no integration added, the Add-In window just fails to show the webex Outlook Add-in.
With webex app.msi version 39.9.2.116 you do see the Add-In DLL present in Outlook > Options > COM Add-Ins.
Using the online calendar scheduling works fine but is a PITA compared to using the Outlook Add-In.
Running newer version 40.8.2.17 webexapp.msi with webex app.msi version 39.9.2.116 already installed removes the Outlook Add-In DLLs which removes Outlook Webex integration.
The old Add-In functionality obviously works with current Office 365 functionality which makes me wonder why it was removed.
I will try and find out if our corporate architecture has run into this yet but I suspect the usual large enterprise change inertia is just using an older client that still "works" without dealing with the need to upgrade to resolve security vulnerabilities.
