Configuring preferences and options in Outlook.com
Yes, I've raised this several times with support now.
None of them have a clue. I have had some irrelevant answers; I was told by one to contact GoDaddy; others have bounced me between Office 365 support (even though it's not software-related) and Outlook.com support (both of which think the problem is a matter for the other).
It is impossible to get anyone's attention. The feature has now been unavailable for several days with no official statement, which seems very unusual and amateurish considering Microsoft has no lack of resources.