Impossible to open Microsoft Teams with the application

Dear @Karine Blanco,

Welcome to Microsoft Q&A. 

Thank you for reaching out, and I’m sorry to hear that you’re unable to open the Microsoft Teams application. I know how disruptive this can be, and I’ll do my best to guide you clearly.

Based on the symptoms you described (“the application will not open”, “restarted the app but still impossible to open”), this typically indicates an issue with the local Teams application installation, application cache, or the desktop environment. Fortunately, these issues can usually be resolved with a few steps.

1. Try closing Teams completely

Sometimes Teams continues running in the background.

• If you are on Windows, right‑click the Teams icon in the taskbar > Quit.
• If you are on Mac, right-click the Teams icon in the dock, and then select Quit or press Command (⌘)-Q. Then try opening Teams again.

2. Clear the Teams application cache

A corrupted local cache is one of the most common causes of this behavior.

On Windows: Close Teams > Press Win + R > type: %appdata%\Microsoft\Teams

Delete all files inside this folder.

On Mac: Close Teams > Open Finder > open the /Applications/Utilities folder and then double-click Terminal.

Enter the following commands, and press Return after each command:

rm -rf ~/Library/Group Containers/UBF8T346G9.com.microsoft.teams

rm -rf ~/Library/Containers/com.microsoft.teams2

Restart Teams.

Try opening Teams again.

3. Reinstall the Teams application

If the installation is damaged, reinstalling is the fastest fix.

Download the latest version directly from Microsoft here: https://www.microsoft.com/microsoft-teams/download-app

Install the app again and try launching it.

4. Use the Teams Web App if you need immediate access

While troubleshooting, you can still join meetings and work normally via:

https://teams.microsoft.com

1. About contacting a human support agent, please try to find the related hotline number to call the frontline: Customer service phone numbers - Microsoft Support 

(Depending on your country or region, when you call the support number, you may hear an introduction of about 30 seconds such as "you can visit the link...". You can ignore this introduction and wait until you are presented with the options. Then press "1" as a business email user, and again "1" for technical help)

If the issue continues even after reinstalling, could you tell me:

• Whether Teams shows any error message or simply does not open
• Whether you are using Microsoft 365 Business / Teams Essentials / Teams Free

Please understand that our initial response does not always resolve the issue immediately. However, with your help and more detailed information, we can work together to find a solution.  

I hope this information helps point you in the right direction. If you run into any issues while trying the steps, or if something still doesn’t feel quite right, please don’t hesitate to reach out again. I’ll do my best to support you however I can.  

Looking forward to hearing back from you with any updates or additional details. 

Warm regards, 

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".    

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.   

If you are unable to open Microsoft Teams after restarting the application, here are some troubleshooting steps you can try:

1. Uninstall and Reinstall Teams: Sometimes, uninstalling the application and then reinstalling it can resolve issues. Make sure to check for any leftover files in the AppData folder after uninstalling and delete them before reinstalling.
2. Clear Cache: Clearing the Teams cache can help. You can do this by navigating to the AppData folder and deleting the Teams cache files.
3. Run as Administrator: Try running Teams as an administrator. Right-click the Teams icon and select "Run as administrator" to see if it opens successfully.
4. Check for Updates: Ensure that your version of Teams is up to date. Sometimes, issues arise from using an outdated version.
5. Check System Requirements: Make sure your system meets the requirements for running Microsoft Teams, especially if you are using a Mac.

If these steps do not resolve the issue, you may need to contact Microsoft support for further assistance. Unfortunately, I cannot provide a direct human contact, but you can reach out to Microsoft support through their official channels.

References:

• How to reset Teams desktop app - is crashing while loading the first run - Microsoft Q&A
• Teams continuously crashing in WIN 11 - Microsoft Q&A