
Fix Microsoft Teams Firewall Blocking Connection: Step-by-Step
If Microsoft Teams won't connect, shows 'connection error', or keeps reconnecting, a firewall is ...
Software troubleshooting desk

If Microsoft Teams won't connect, shows 'connection error', or keeps reconnecting, a firewall is ...

You’re trying to start Windows Search or an indexing service, and you see an error like “Port 80 ...

You see a OneDrive sync error that says "file in use" or "the file is open in another program." T...

You open Windows Security and see a yellow warning: "Invalid configuration" or "Page not availabl...

You launch Windows Defender Security Center or try to run a scan, and you see a proxy error—somet...

You double-click Command Prompt (cmd.exe) and a black window flashes on screen—then disappears. T...