Report suggests that an 'ad' for Microsoft Teams may have broken the Windows 11 desktop and taskbar

Windows 11 Install Fewminutes
Windows 11 Install Fewminutes (Image credit: Daniel Rubino / Windows Central)

What you need to know

  • Some Insiders last night testing Windows 11 lost the desktop, Start menu, and taskbar after a reboot.
  • Initial speculation tied the bug to yesterday's Beta and Dev channel releases.
  • A new analysis suggests that a cloud-based Microsoft Teams pop-up may be responsible.
  • The analysis calls into question how one failed cloud service can, reportedly, "bring the Windows shell to its knees."

Last night was a doozy for those on the Windows Insider program (Beta or Dev Channels) testing Windows 11. Many people restarted their PCs only to find the Windows 11 desktop, including the Start menu and taskbar completely missing. Users could access the Task Manager and command prompt to help navigate around, but that was it.

A few workarounds appeared, including an official one from Microsoft, that all interfered with the device's ability to properly communicate with Microsoft's servers, which raises the question: What exactly was it that caused the problem?

Microsoft didn't go into detail, just remarking it was "a server-side deployment that went out to Insiders."

However, a new report suggests it was even dumber: A pop-up notification for Microsoft Teams notifying you of the service and how to sign into it.

Daniel Aleksandersen, who writes on Ctrl blog, explains:

I took a closer look at what got downloaded and caused the Windows desktop shell to become unresponsive … The problem wasn't caused by an update delivered through Windows Update. (That would have been more understandable.) Instead, it was caused by a small file downloaded by a Windows component called IrisService. Iris is a part of Windows Spotlight (the Bing wallpaper of the day; and tips, promotions, and suggestions on the Lock screen).Based on the Microsoft-provided workaround, I narrowed the problem down to a registry key that contained a serialized JSON blob. The blob contained an advertisement for Microsoft Teams. The messaging and imagery in the promotion were identical to the panel you get when you press the Windows key + C on a Windows account not already set up with Teams. It's unclear if it's this exact promotion, however.

Some of these points line up with my own experience. I had to restart the PC for new Razer drivers being installed on my main desktop, not yesterday's Beta Channel update, as those drivers superseded its installation. Nonetheless, my PC suffered the same fate despite not going through the OS update. It may also explain why not all PCs were experiencing it (my three laptops were just fine).

Source: Microsoft (Image credit: Source: Microsoft)

But Aleksandersen goes on to raise a good question:

There's an enormous elephant in the room, though: how Microsoft could have let this happen? Yes, this is a beta build for early adopters. Yes, rough edges and productivity losses are expected.However, that doesn't answer why the Windows shell was so poorly architect in the first place. How come that it would stop responding just because of one failed cloud service? It's not a crucial cloud service either, and the computer became useless because of a single JSON blob with an advertisement.

Assuming the analysis is accurate, Aleksandersen remarks that "…unimportant cloud-dependent systems must be isolated from the core operating system so that they can't bring the Windows shell to its knees."

I must caution that this is but one analysis of last night's problem. Still, until Microsoft comes out with a detailed explanation — and clarifies how this won't happen again — critics of Microsoft's cloud-based approach may continue to make a good point about the system's apparent weakness.

And whatever the cause, yesterday's problem was one of the most serious to hit the Windows Insider program just a month before the release of Windows 11.

Daniel Rubino

Daniel Rubino is the Editor-in-chief of Windows Central, head reviewer, podcast co-host, and analyst. He has been here covering Microsoft since 2007 when this site was called WMExperts (and later Windows Phone Central). His interests include Windows, Microsoft Surface, laptops, next-gen computing, and for some reason, watches. Before all this tech stuff, he worked on a Ph.D. in linguistics and ran the projectors at movie theaters, which has done absolutely nothing for his career.

  • This is an interesting finding, if it's true then it is indeed a question of weaknesses of how they architect several Windows shell components that something a simple bug like this, can cause the OS unusable for most users. Good thing this only happened on Insider build and not on production build. This issue was weird in the first place, since the last time I used the PC, I didn't get Windows Update before I shut down and no messages indicating it was. Then next morning, turn on my PC and suddenly my Taskbar and the whole shell simply don't load completely. I thought it just a normal Insider bug, which can happen, but restarting explorer didn't work and even using DISM tool didn't either, system restore, etc. All that hassle and the workaround/fix was to adjust the date at least 2 days ahead and restarted. If this is true, we have to wait if Microsoft will be transparent about this. This will certainly be used as a weapon to criticize Microsoft efforts on cloud tech with Windows and Windows 11 in general. But yeah, it seems like the new web tech implemented in Windows 11 is certainly in its infancy, but can be scary with just a server-side issue somehow can affect unknwon number of client PCs. Windows Widget for example is a purely web-based feature. Though its not bad being a web based, but how they architect is bad. It doesn't seem to work offline and every time I open Widget, there is like a second or so delay before the Widgets appear in view after the pane slides in. Not to mention a several seconds to load after cold boot. This is certainly inferior behavior compared to Live Tiles which is the code is localize and the content is the only will get fetch from the web, but not always. Windows 11 certainly needs to be hardened against these server-side bugs that can affect the actual operation of the OS.
  • All good points, especially about Widgets — I've seen that too, and doesn't look great. I feel 10X, which was built from the group up, may have been less vulnerable to these things. But Windows 11 is built on Windows 10, which brings a lot of legacy to the game, which may be the problem here — rushing new tech into an old system.
  • Yeah, maybe because Windows 11 development is relatively "rushed" compared to Windows 10X which was in development for years, which is understandable since it is an OS from the ground up, or at least for what I read here from Windows Central, it can be traced for the next version of Windows 10 Mobile with C-Shell development which we know what happen. Thinking that what you said about rushing new tech. I guess that sort of make sense why Windows 11 Widgets is such a well, a glorified News & Interest with just an ability to add widgets, which is basically a News cards in a way. If they thought about Widgets way before they thought of killing Live Tiles, probably we may have a more robust, more localized and likely already open to 3rd-party Widget system for Windows 11. Based on Windows 10X builds in the past, there was no info about Widgets before, or at least what I remember. Idk if Zac already had info about Widgets development before Windows 11. Because it does feels like an afterthought for Windows 11. So the web-based tech on it is pretty early and adding the legacy thing of Windows desktop OS, things may not work too well until they really put more effort on it. Because of the Widgets shortcomings, I admit I don't use it as much often due to many reasons. I am a fan of having dashboard interface to an OS, but Windows 11 implementation isn't it, at least for now. Though not all web based are that too bad, the new Teams so far is great and architected it in such a better way that it is definately better performant than the old one. But alas it is just an app, usually independent to OS. This shell based with web tech on it can be a huge issue depending on the architecture and how robust it is, not affecting the whole shell with it from a mere simple server-side changes and issues.
  • Maybe someone is trying to tell Ms that we would like to be able to move the Taskbar again.
  • Seems it is marginally related to that silly 'chat' feature foisted upon us. It's silly to me because I have no desire to 'chat' with my family and friends on my domain connected enterprise laptop. I do have a need to chat with colleagues in my enterprise TEAM. Guess they hadn't considered that since you can't associate the taskbar chat with a business TEAMS account.
  • I'm sure that will change by win11 22h2 they'll have it so you can use a work acct with it. They did the same thing for many things sticky notes, quick assist, etc. Thing always come out for personal first then when they are ironed out they add in the business side.
  • I hope you're right. My biggest concern/problem with MS right now is about the muck they're creating with the differential handling of personal and business accounts. E.g., OneDrive for business is completely different architecture from OneDrive, but it's made to look about the same and the name is obviously the same. This is also the case with Teams, Outlook, and a few other things. They're creating deeper and deeper problems for themselves by insisting on this hard distinction. None of the pieces play nice with each other and we're stuck with weird problems like you can have one personal Teams account and one Work account, but not 2 work accounts (a must for any consultant working with more than 1 client). The Taskbar Teams issue is personal. Personal Teams can't talk with Business Teams. They assume you run both as separate unrelated apps. So for the Taskbar to work for both they'll need to merge these or give 2 separate chat options. Neither of those seems likely in the next year or so.
  • Sigh.... this yet again another reason for Microsoft to rehire the QA team and programmatic testers. They could have avoided this entirely had they already done so. Microsoft needs to stop being a stubborn mule and rehire them damn it. Screw the damned bean counters.
  • Oh dang, win 11 will have cloud based pop up ads...
  • This is the point of testing. Hopefully, Microsoft will learn and add more validation to any data downloading from their new and existing services.