When you find Microsoft Teams not opening on Windows, the culprit is almost always local: a damaged cache, a process left hanging in the background, or the WebView2 component that draws the interface. Fully quitting the app and then clearing its cache fixes most cases in five minutes. Before you touch anything, a detour through the web version will tell you whether the service itself is at fault, and will let you join your meeting while you repair the app.
In short: the quick fix
- Open teams.microsoft.com in Edge or Chrome. If the web version works, the service is fine and the problem is on your PC.
- End every Teams process in Task Manager (Ctrl + Shift + Esc), then relaunch.
- Clear the cache: delete the contents of
%userprofile%\appdata\local\Packages\MSTeams_8wekyb3d8bbwe\LocalCache\Microsoft\MSTeams. - Still stuck: Settings > Apps > Installed apps > Microsoft Teams > Advanced options > Repair, then Reset.
- Only after that, repair WebView2 and reinstall Teams.
Microsoft Teams not opening: recognizing the problem
A startup hang takes several forms, and each one points to a different cause.
The most common: a window opens, entirely white, sometimes with the purple title bar and nothing underneath. It stays that way indefinitely. Second variant, the Teams logo appears with a loading indicator that spins forever. Third case, nothing happens at all: you click the icon, the cursor animates for a second, no window appears, even though Task Manager clearly shows an active ms-teams.exe process. Finally, Teams may open on a generic error screen, such as “Something went wrong” or “We’ve run into an issue”, or loop on the sign-in window.
Two generations of the client still coexist on some machines. The new Teams is a packaged app (MSIX format) whose process is called ms-teams.exe. The older classic Teams runs as Teams.exe and stores its data elsewhere. The steps differ, which is why it helps to identify which one you are using: search for “Microsoft Teams” in Settings > Apps > Installed apps. The word “classic” or the presence of a “Teams Machine-Wide Installer” gives away the old client.
Why it happens
The new Teams is not a conventional program. It is a shell that displays a web interface using WebView2, the Microsoft Edge rendering engine shipped as a separate component. If WebView2 is missing, damaged or blocked by security software, the shell opens but has nothing to paint: that is the white screen.
The second source of trouble is the cache. Teams stores temporary files, session tokens and settings locally so it can start quickly. A hard shutdown, an interrupted update or a full disk can leave those files in an inconsistent state. On the next launch, the app reads data it no longer understands and freezes.
The third cause is less well known: the Windows environment itself. Microsoft documents several situations where the new Teams refuses to start because user profile folders (AppData, the Internet cache, the temp folders) are redirected by a reparse point, meaning a link that points to another location, or because permissions on those folders have been changed. This mostly affects corporate machines with folder redirection or roaming profiles.
That leaves outside causes: a proxy or antivirus inspecting encrypted traffic, a VPN, a faulty graphics driver, a Windows session whose saved credentials are stale. And of course an outage on Microsoft’s side, which is rarer than people think for this particular symptom: a service outage usually stops you from signing in or sending messages, not from displaying the window.
Before you start
Your chats, files and teams are stored in the cloud. None of the steps below deletes them. You will, however, lose your local settings (theme, selected audio devices, custom backgrounds) and you will have to sign in again: keep your password and your phone for two-factor authentication within reach.
One trap to know about if you plan to call on your IT department: clearing the cache also deletes the diagnostic logs. Microsoft in fact advises against it for missing messages or missing channels, precisely because it wipes the useful traces. If you intend to open a ticket, copy the cache folder somewhere else before you empty it.
Some steps require administrator rights. On a company-managed PC, stop at solution 4 and hand over.
Solution 1: check the service status and switch to Teams on the web
Do this first. No risk, two minutes.
1. Test the web version
Open teams.microsoft.com in Edge or Chrome and sign in. If your chats appear, the service is working and so is your account. You can work, join a meeting and share your screen from the browser while you repair the app.
2. Check the service status
The public page status.cloud.microsoft reports major Microsoft 365 incidents. The @MSFT365Status account on X relays the same information. Admins get a finer view in the Microsoft 365 admin center, under Health > Service health.
3. Interpret the result
The web version fails too and an incident is declared: wait, nothing you do on the PC will change anything. The web version works: move on to solution 2. The web version fails with no declared incident: try another network, for example your phone’s hotspot, to rule out a block by your network’s proxy or firewall.
Solution 2: quit Teams completely
Use this as soon as the window stays white or doesn’t appear. No risk.
Clicking the X does not quit Teams; the app keeps running in the notification area. And when it is frozen, right-clicking the icon > Quit doesn’t always respond.
1. End the processes
Open Task Manager with Ctrl + Shift + Esc. On the Processes tab, select Microsoft Teams and click End task. On the Details tab, check that no ms-teams.exe line remains (or Teams.exe for the classic client).
Faster, in a Terminal or Command Prompt window:
taskkill /IM ms-teams.exe /F2. Relaunch
Wait about ten seconds, then reopen Teams from the Start menu. If the hang came from a zombie process, for example after waking from sleep, the window appears normally.
If the screen stays white, restart Windows once before going further. A full restart (Restart, not Shut down) also relaunches the update services that Teams and WebView2 depend on.
Solution 3: clear the Teams cache
This is the step that gets the most machines going again. Low risk: local settings lost, slower first start while the cache rebuilds.
1. New Teams
Quit Teams as described above. Press Windows + R, paste this path and confirm:
%userprofile%\appdata\local\Packages\MSTeams_8wekyb3d8bbwe\LocalCache\Microsoft\MSTeamsSelect everything in the folder (Ctrl + A) and delete it. Don’t delete the MSTeams_8wekyb3d8bbwe folder itself, only what sits in the location you opened.
2. Classic Teams
Same principle, with this path:
%appdata%\Microsoft\Teams3. If Windows refuses to delete a file
A “file in use” message means a Teams process is still running. Go back to Task Manager, end it, and try again.
Check: on restart, Teams shows the sign-in screen and then loads your teams. The first launch takes noticeably longer than usual, which is normal.
Solution 4: repair, then reset the app
Use this if clearing the cache by hand did nothing. Applies to the new Teams only.
1. Open the advanced options
Settings > Apps > Installed apps. Find Microsoft Teams, click the three dots on the right, then Advanced options.
2. Click Repair
Windows checks the app package without touching your data. Relaunch Teams to test.
3. Click Reset
If the repair isn’t enough, the Reset button just below erases all of the app’s local data. It is the equivalent of a full cache clear carried out by Windows, and it is the method Microsoft recommends first for the new Teams.
Check: Teams restarts as it did the first time it was installed.
Solution 5: repair or reinstall WebView2
Use this when the window stays white despite a clean cache, or when other recent apps (widgets, the new Outlook) show the same blank. Low risk.
1. Check that it is there
In Settings > Apps > Installed apps, search for “WebView2”. You should find a Microsoft Edge WebView2 Runtime entry. On Windows 11, the component is part of the system. On Windows 10, it is present on the vast majority of machines, but not all.
2. Run a repair
Click the three dots next to the entry, then Modify, and choose Repair. An Internet connection is required.
3. Reinstall it if it is missing
Download the Evergreen installer from the WebView2 page on Microsoft’s developer site (developer.microsoft.com/microsoft-edge/webview2). For a silent deployment:
MicrosoftEdgeWebview2Setup.exe /silent /install4. Update Windows and Edge
WebView2 updates through the same mechanism as Edge. A machine whose updates have been blocked for a long time ends up with an engine too old for Teams. Run Windows Update, install everything, restart.
Check: after the restart, the Teams window shows content instead of white.
Solution 6: clean up saved accounts and credentials
Use this when Teams loops on sign-in, shows a code such as 0xCAA20004 or 0xCAA70004, or hangs right after you enter the password. Moderate risk: other Microsoft 365 apps will ask you to sign in again.
1. Remove the Teams credentials
Open Control Panel > User Accounts > Credential Manager > Windows Credentials. In the Generic Credentials list, remove the entries whose name contains “msteams” or “MicrosoftOffice”.
2. Reconnect the work account
In Settings > Accounts > Access work or school, find the account in question. If it was simply added (and not used to join the PC to the company domain), click Disconnect, restart, then add it again. On a PC joined to the organization, don’t touch this setting without your administrator’s approval: you could lose access to company resources.
3. Check the date and time
A clock that is off by a few minutes is enough to make authentication fail. Settings > Time & language > Date & time: turn on Set time automatically and click Sync now.
Solution 7: uninstall and reinstall cleanly
Use this when everything else has failed on this machine. Allow a quarter of an hour.
1. Uninstall Teams
Settings > Apps > Installed apps > Microsoft Teams > Uninstall. In PowerShell, for the current user:
Get-AppxPackage *MSTeams* | Remove-AppxPackage2. Remove the leftovers of the classic client
If the app list still contains Microsoft Teams classic or Teams Machine-Wide Installer, uninstall them as well. The latter is the machine-wide installer: as long as it stays in place, it reinstalls the old client at every sign-in, which explains many a “Teams keeps coming back by itself”.
3. Delete the leftover folders
Empty the two cache locations given in solution 3, then restart.
4. Reinstall
Download the client from the official Microsoft Teams site or install it from the Microsoft Store. Launch it and sign in.
Solution 8: rule out the graphics driver, the network and security software
These causes are in the minority, but they are the ones that survive a reinstall.
1. Graphics driver
A white or black window that appears after waking from sleep or plugging in an external display points to the driver. The Windows + Ctrl + Shift + B shortcut restarts the graphics driver on the fly: the screen flickers for a second. If Teams then displays, update the driver from the website of the PC or graphics card manufacturer (Intel, AMD, NVIDIA), not just through Windows Update.
2. Proxy, VPN and traffic inspection
Turn off the VPN and test. On a corporate network, a proxy that decrypts HTTPS traffic regularly breaks Teams loading. The hotspot test settles it: if Teams starts on mobile data and not on the office network, the machine is innocent. Microsoft publishes the list of addresses and ports to allow for Microsoft 365, which you can pass on to the network team.
3. Antivirus
Temporarily turn off real-time protection in your third-party antivirus, launch Teams, turn it back on. If the hang disappears, add exclusions for ms-teams.exe and msedgewebview2.exe rather than leaving protection off.
4. Corrupted Windows profile
Create a local test account (Settings > Accounts > Other users > Add account), sign in to it and launch Teams. If it starts, your usual profile is the problem: redirected folders, modified permissions, TEMP or TMP variables pointing to an unusual location. That is the territory of the next solution.
Solution 9: for administrators
1. Run Microsoft’s diagnostic scripts
Microsoft provides a script, TeamsLaunchCheck.ps1, that checks the documented causes of launch failure in one pass: reparse points on the Cookies and Cache folders, TEMP/TMP variables, read permissions on AppData, full control for SYSTEM and the Administrators group, SYSAPPID permission on the installation folder, AllowAllTrustedApps policy. A quick manual test of the first point:
(gp ([environment]::getfolderpath("Cookies"))).Attributes -match 'ReparsePoint'
(gp ([environment]::getfolderpath("InternetCache"))).Attributes -match 'ReparsePoint'A True result identifies a redirected folder. The default values are restored in HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders. A second script, available at aka.ms/NewTeamsReadinessCheck, checks the installation prerequisites and can be pushed through Intune.
2. Check the app deployment policies
In the Group Policy Editor, under Computer Configuration > Administrative Templates > Windows Components > App Package Deployment, settings that prevent non-admins from installing packaged apps or that turn off the installation of trusted apps block Teams. The matching keys are under HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\Appx.
3. Redeploy in bulk
The teamsbootstrapper.exe tool installs the new Teams for all users of a machine, present and future:
.\teamsbootstrapper.exe -pOffline, add the path to the package: .\teamsbootstrapper.exe -p -o "c:\path\to\teams.msix". Always use the latest version of the tool. Delivery Optimization download mode 100 (Bypass) is not supported, and a disabled Delivery Optimization service prevents updates.
4. Don’t modify the package
Any alteration of the files under %programfiles%\windowsapps causes crashes, unexpected closures and update failures. “Cleanup” tools and some hardening scripts are responsible for this.
5. Collect the logs before clearing the cache
If the window still displays, the Ctrl + Alt + Shift + 1 shortcut generates the support files in the Downloads folder. The same goes for right-clicking the notification area icon > Collect support files. When nothing displays, copy the Logs subfolder from the new Teams cache location. Timestamps are in UTC.
Summary table
| Symptom | Likely cause | Solution to try |
|---|---|---|
| Persistent white window | Corrupted cache or faulty WebView2 | Solutions 3, 4 then 5 |
| No window, process running | Process frozen in the background | Solution 2 |
| Endless loading on the logo | Cache, filtered network | Solutions 3 and 8 |
| Sign-in loop, 0xCAA… code | Stale credentials, clock, conditional access | Solution 6 |
| “We’ve run into an issue” | WebView2 missing | Solution 5 |
| Teams on the web fails too | Service outage or network | Solution 1 |
| Works on another Windows profile | Profile or redirected folders | Solutions 8 and 9 |
| White after waking from sleep | Graphics driver | Solution 8 |
| The old Teams reinstalls itself | Machine-Wide Installer left in place | Solution 7 |
If nothing works
Carry on with the web version, which covers most needs, and pass the case to your support team with precise details: Windows version (winver command), exact text of the message, result of the test on another profile and on another network, list of what you have already tried, collected logs. Those five pieces of information save three rounds of back-and-forth.
On the admin side, open a support request from the Microsoft 365 admin center. Attach the logs and the output of TeamsLaunchCheck.ps1. If the script reveals a missing SYSAPPID permission, Microsoft recommends deleting and recreating the user profile. As a last resort on an isolated machine, repairing Windows with an in-place upgrade keeps files and apps.
Keeping it from happening again
Let Teams and Windows update themselves. The client updates on its own in the background and Microsoft expects users to stay on a recent version; an alert appears in the app when the installed version is more than a month old.
Quit Teams before turning off the PC rather than forcing a shutdown, and keep free space on the system drive. Ban cleanup utilities that purge AppData or the temp folders while Teams is running.
In a company, exclude the Teams cache folder from folder redirection and test any new proxy or antivirus rule on a pilot machine before rolling it out.
Frequently asked questions
Does clearing the Teams cache delete my chats?
No. Messages, files and teams are kept on Microsoft’s servers. Only local settings and diagnostic logs disappear.
Where is the new Teams cache located?
In %userprofile%\appdata\local\Packages\MSTeams_8wekyb3d8bbwe\LocalCache\Microsoft\MSTeams. The classic client uses %appdata%\Microsoft\Teams.
What is the difference between Repair and Reset?
Repair checks the app without touching the data. Reset erases all local data and signs you out.
Teams works in the browser but not in the app. Why?
Because the service and your account are healthy. The fault lies with the installed client: cache, WebView2 or the Windows environment.
Should the classic Teams still be installed?
No. The classic client is no longer maintained and its presence keeps conflicts alive. Uninstall it, along with its machine-wide installer.
If you still find Microsoft Teams not opening after these steps, describe in the comments what you see on screen, your Windows version and the result of the web version test: that is often enough to pin down the cause.
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