Nope..... that was something called Live Mail.
What version of Outlook are you using? Perhaps earlier than 2013?
Following is the email from Microsoft
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Dear Outlook.com customer,
Earlier this year, Microsoft introduced the new Outlook.com, which provides a business-class email experience to help you stay connected and get more done. Now that you have been upgraded to the new Outlook.com, it’s necessary that you reconnect Outlook 2016 or Outlook 2013 to your Outlook.com account. As someone who has an Outlook.com email account connected to a desktop version of Outlook 2016 or Outlook 2013, you’re receiving this final reminder because you have not yet reconnected your account.
What to do: Reconnect your desktop version of Outlook to your Outlook.com account to ensure uninterrupted email access. If you do not reconnect your account, your Outlook.com emails will soon stop syncing to Outlook 2016 and Outlook 2013. Once you reconnect, your Outlook.com emails will resume syncing to your desktop version of Outlook.
For detailed instructions and help on how to reconnect your account, please visit the official Microsoft support website at
https://go.microsoft.com/fwlink/?linkid=837697.
Note that this change only affects any Outlook.com accounts you are accessing via Outlook 2016 or Outlook 2013; you do not need to reconnect to your other email accounts, such as Office 365, Exchange, or other third party email accounts. You can also continue to send, receive, and access email from your Outlook.com account on the web via any popular web browser.
We recognize that reconnecting your account is inconvenient, but this step will ensure that you are able to take full advantage of the new Outlook.com over a more secure and reliable infrastructure. If you have any questions not answered by the support article above, please contact customer support at:
https://support.office.com/home/chat.
Thank you for being an Outlook.com customer,
The Outlook.com team
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