Teams phones and firewalls
A customers network people created a separate vlan for the Teams phones. When trying to use either the "Web Sign-in (Cloud)" or "CAP provisioning", they get "Web Sign-in (Cloud) failed Signing Out". Are the firewall ports required for the phones the same found in the full IP and URL list? They never get the web address link and code to sign in.
Skype sign-in failed on MTR breaks after installing KB4565351
Beware guys, this updates that was release yesterday will break the Skype for Business sign in on your MTR if your company is still running in the mix mode where Skype is still set as default. The solution now is to uninstall this updates.