How can I prevent Microsoft Teams from automatically restarting without my permission after updates?

Question

So this is driving me absolutely nuts. I'm using Microsoft Teams, and every week or so, it restarts, and tells me that I'm now working with the latest version of Teams. This will usually happen when I've organized different chat windows on different desktops according to different topics, and of course Microsoft just wipes it all out by restarting without my permission.

So, I went on to try and figure out how I can avoid it. There's not much information on the internet, but what I found is the following:

• If you install it for all users (and add some registry key to make it look like your computer provides VDS, because otherwise it won't work), it shouldn't automatically update anymore. The problem is, though, that you can't update it at all anymore, which is not what I want, either, (I want the updates, I just don't want it shoving them down my throat and restarting MS Teams without my consent) at least in theory. Here's the deal though: I tried that, and the darned thing still restarted for updates. I have no clue how.
• I've tried changing the settings in the settings.json file (in AppData - Roaming - Microsoft - Teams), but somehow, it constantly reverts those settings back to the default.
• I've tried running a batch file in the background, changing the value "silentUpdateTriggered" to false every minute, but that doesn't work either.
• I've watched how it updates Teams, and noticed that it creates the "DownloadedUpdate" folder where it downloads the update, then deletes it afterwards. So, I created a file called "DownloadedUpdate" and made sure the permissions were such that MS Teams can't do anything about it. Here's where things get funny: MS Teams still restarts, but hasn't updated. Seriously, the thing says it restarted for updates, but the executable is still the exact same executable from back before the update. The log even says that it couldn't download the update. I am at a loss for words.

Does anyone have any idea how to prevent this from happening? This is so ridiculously infuriating.

Answer 1

I have not done this for Microsoft Teams, but I did for other Microsoft stuff with similar (if not as pervasive as yours) problems.

What I did was inspect the DNS queries issued by the software to get the update information, then map those names to 127.0.0.1 in the hosts file. Then, usually on Saturday, I have a task that sets the names back to normal. This allows updates to be pushed through, and sets aside Sunday to solve any issues they might cause.

In my case, the software never required an active Internet connection, but Microsoft Teams does, so it might be that the update server and the command-and-control network are one and the same. In that case I'm afraid that, barring a HTTPS MitM firewall that rewrites update queries, there's little or nothing that can be done.

One thing you probably already noticed, but still -- the link that starts Teams does not start Teams, it actually starts an update service ("Update.exe"). The real Teams app is called Teams.exe, but it's being link-hijacked by the update manager.

I fully expect Microsoft to soon switch to active malware/rootkit techniques to keep updating whenever they want, but they haven't done so yet.