Hi Neil,
Thanks for contacting us and sorry for the inconveniences,
Here are some solutions to try:
- Disable MS Teams from the startup apps list on your PC in the Settings app. You can do this by going to **Start > Settings > Apps > Startup** and turning off the toggle for MS Teams.
Answered by Rodell in the thread https://answers.microsoft.com/en-us/msteams/forum/all/how-do-i-stop-teams-from-starting-on-its-own/b1567635-ff5d-46d4-9bc4-acc8498349d9
"- Uncheck the auto-start option in the MS Teams settings. You can do this by right-clicking the MS Teams icon in the system tray and selecting **Settings**. Then, uncheck the box for **Auto-start application**. You may also want to uncheck the boxes for **On close, keep the application running** and **Register Teams as the chat app for Office**."
- Block MS Teams from the firewall settings. You can do this by going to **Start > Settings > Network & Internet > Windows Firewall > Advanced settings**. Then, create a new outbound rule for MS Teams and set the action to **Block**. Note that this may affect the security and functionality of MS Teams, so use it at your own risk.
To fix the issue with MS Teams Classic not opening, you can try the following steps:
- Clear the cache files of MS Teams Classic on your PC.
- Uninstall and reinstall MS Teams Classic from the Microsoft website or the App Store.
Let me know if this helps or if you need further assistance.
Regards,
Sola
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