I'm having below error message when attempt to login teams via IE/chrome/firefox. However, seem to be fine with Microsoft Edge.
I have whitelisted the IP provided by Microsoft in our Firewall, why do we still having this issue?
@min777 So if it works Microsoft Edge there is probably no problems with your firewall. Does Teams client work (download it at https://teams.microsoft.com/download).
Microsoft Edge will use the proxy settings in Windows, make sure that you have the same proxy settings in the other browsers. But the recommendation is to bypass proxies for all Teams traffic.