My friend experienced en arror today (21.01.2021) that means "Login flailed. Please be sure that you are online." or something like that.
What we tried already:
-End Win10 Firewall (he doesnt have an Antivirus installed)
-Java (and the MinecraftLauncher.exe) are now checked under "Private" in the Firewall
-Login on an other PC (worked!)
-No programms like MCLeaks are activated
-Reinstalled the game several times and deleted the .minecraft folder
-logging in on minecraft.net (didnt work on his PC)
Thank you for your report!
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