Additional features, settings, or issues not covered by specific Microsoft Teams categories
Log out of your Teams account.
Launch the Task Manager and locate all Microsoft Teams processes running in the background.
Right-click on each process and select End task.
Reboot and recheck.
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Update graphic card driver. Visit the support site of the manufacturer to download and install the latest driver.
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A number of users confirmed they fixed the black screen issue on Teams by deleting the settings.json file.
Navigate to C:\Users\UserName\AppData\Roaming\Microsoft\Teams. Locate the settings.json file and delete it.