Additional features, settings, or issues not covered by specific Microsoft Teams categories
Most likely the reason is the meanwhile un-supported TLS 1.0 and 1.1. but it may still be the setting for some PowerShell versions. To work around:
Set-ItemProperty -Path 'HKLM:\SOFTWARE\Wow6432Node\Microsoft.NetFramework\v4.0.30319' -Name 'SchUseStrongCrypto' -Value '1' -Type DWord
Set-ItemProperty -Path 'HKLM:\SOFTWARE\Microsoft.NetFramework\v4.0.30319' -Name 'SchUseStrongCrypto' -Value '1' -Type DWord
Then exit and re-start PowerShell as admin.
It did the job for me.