Wow - talk about a repetitively and continuously MISNAMED subject. Only MS could think THIS TITLE "Basic Auth and Exchange Online" is an appropriate name for breaking nearly every legacy email client that interacts with Exchange. The utter ARROGANCE of MS knows no bounds. NO ONE is reading the messages with titles like this, unless they are IT professionals getting paid to read every single message. (Perhaps 10% of your customers.) I would call it sheer stupidity, but in this case it actually appears purposeful, as in literally hiding from the wrath of your customers, but claiming you notified them. THIS CANNOT BE AN ACCIDENT- no multi-billion dollar company is this inept. You could try: "ALL YOUR OLDER EMAIL CLIENTS ARE GOING TO BREAK - 'CAUSE WE ARE GOING TO DISABLE THEM - YOU'RE WELCOME, MICROSOFT". That might be read. It literally appears that Azure just DOES NOT WANT CUSTOMERS - else hires the absolute dumbest messaging people EVER.