Teams Add-in is missing in Outlook on a terminal server

[AtanasM]

The Outlook Meeting Add-In is enabled, but the button to create a new meeting is missing.

The mailboxes are hosted on-premises and there is an Exchange hybrid. The issue exists since 28.02.2021, after an update of Teams on both terminal servers.
Checked and the calendar function is not available in Teams. It was not available in the past as well.

The issue doesn't exist on Windows 10 computer.
Error message while running Sara tool: "Microsoft Teams is not installed".

But I noticed that the add-in in Outlook refers to / AppData / Local / Microsoft / Teams and not to / AppData / Roaming /.
I also deleted this folder. And then restarted Teams and Outlook. A new Teams folder has been created under Roaming / Microsoft, but the add-in still refers to Local, even if there is no longer a Teams folder there.

Terminal server: Windows Server 2016 Standard
On Prem server: Microsoft Exchange Server 2016 Cumulative

Outlook version on the server: Microsoft Office Professional Plus 2019, 1808 (Build 10371.20060 Click to Run)
Outlook version on a Windows 10 computer: Microsoft Office Standard 2019, 1808 (Build 10371.20060 Click to Run)

Teams version on the server: 1.4.00.2879 (64-Bit), Citrix HDX optimized.
Teams version on the Windows 10 computer: 1.4.00.4167 (64-Bit)

Re-installed Teams, but it didn't solve the issue.
Created a new Outlook profile, but it didn't solve the issue.

[#2]

https://docs.microsoft.com/tr-tr/microsoftteams/teams-add-in-for-outlook

[#3]

How this link helps in the described problem? He clearly states that the button is missing.
We have an identical problem in very much identical setup. The Teams add-in is listed as active and loaded in Outlook on the terminal server, but no button for Teams meeting. Same users on their workstations have this button. So, can anyone produce an idea why? Please, do not send an instruction how to enable add-in Outlook or check registry settings for loading add-in, all that is already checked.
Thank you
I wonder if anyone can

[#4]

Having the same Issue, anyone have a solution yet?

[#5]

We had similar issue, and turned out that even though we do not use Teams within the terminal server (too resource hungry), we still have to get users to sign into Teams within the terminal server once a month, and ensure Teams was up to date, once updated, and outlook restarted the button reappears, we then ensure staff quit teams and it is not set to auto start upon login within the terminal server - hope this helps