Why can't I see the Microsoft Teams Meeting add-in for Outlook?

Here is one user also without the Add-in. When looking for the Teams' installation log under:

C:\Users\<userID>\AppData\Roaming\Microsoft\Teams\logs.txt

That says for me:

Fri Dec 07 2018 10:53:47 -- info -- Meeting policies synced. Enable Outlook Addin for Teams Meeting: true 
Fri Dec 07 2018 10:53:47 -- info -- Current Outlook Version: 16 
Fri Dec 07 2018 10:53:47 -- error -- Error in registering outlook meeting addin. Errorcode:[object Object] 
Fri Dec 07 2018 10:53:47 -- event -- name: meeting_addin_registration_failed, result: 2, reason: com_registration_failure, contextForAddin: meetingPolicySettingsSynced,  
Fri Dec 07 2018 10:53:48 -- info -- Comparing app version 1.1.00.31860 with critical version 1.0.00.6903 
Fri Dec 07 2018 10:53:48 -- info -- Comparing app version 1.1.00.31860 with minimum version 1.0.00.25152 

Kind of strange is also when you take a look the Add-in version from the folder, it says:

C:\Users\<userID>\AppData\Local\Microsoft\TeamsMeetingAddin\1.0.17123.7

But at the same time the Teams version is: 1.1.00.31860.

Some very strange way I thought they should be the same, but obviously not...?