Can't access Outlook.com with Microsoft account with @cornell.edu email address

I've had a Passport / Live Id / Microsoft account for many, many years.  I have all my Microsoft-related context associated with this account, including a Windows Phone.  This account's main email address is an @cornell.edu email address.

Some time ago, I went to Outlook.com with this live id and created a bunch of email aliases, thinking that I might switch my primary email address to an @outlook.com one at some point in time.

Recently, I've been unable to access Outlook.com.  I get the following error:

This account can't be used to access Outlook.com

You're currently signed in with an Office 365 email account, which can't be used with Outlook.com. Please clickhereto sign out of your Office 365 account, then use another Microsoft account to sign in to Outlook.com (for example, your hotmail.com, live.com, or msn.com account).

I have no relationship to Office365.  However, I suspect that the cause is that the actual Cornell U recently signed up for that service for its email domain, and for some bizarre reason that rendered my own (alumni) cornell.edu account unusable with Outlook.com.

I'm also unable to access my Contacts through the web (I see the same error).  My WP7 devices and Win8 desktop can still use Live contacts, so I assume the API still works.  It's a weird mess.

One of the solutions I considered doing was to switch my live id to my outlook.com alias.  However, since I'm now unable to access the Outlook.com interface, I'm unsure as to how to do that.  If I go to https://account.live.com/ChangeId.aspx, the only domain options I get are live.com and hotmail.com.  If I enter an outlook.com alias as a "different address", it says:

You can't use @outlook.com in your Microsoft account email address. Please try a different email address.

Suggestions?