Hi @Renaldo ,
Does anyone else have the same issue in your organization?
Have you tried to change another device to access Teams?
In this case, we recommend you try to perform a clean boot in Windows to block the third party application that affect Microsoft Teams login normally. For more details about how to perform a clean boot, you can learn it from:
In addition, please check if you have opened UDP port 3478-3481 in your firewall.
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