Microsoft had put up a notice as follows:
Reconnect Outlook to Outlook.com
If you need to reconnect Microsoft Outlook desktop email client to your Outlook.com account, you have two options:
Create a new Profile in Outlook
To create a new profile, open your Control Panel, type Mail in the search box and click on the result – Mail that you see, to open the following box.
Click on Show Profiles and then on the Add button.
Give the profile a name and select OK.
The following box will open, where you can set up your outlook.com as usual.
Click on the Add Account link to open the following wizard and fill in the details. Click on Next and follow the wizard.
Remove the email account & recreate it
If you use Microsoft Outlook to sync several email accounts, you will have to delete the account and create a new one. To remove the email account from Outlook, open Outlook, click on the File tab > Account Settings. Now select the email account and then click on the Remove link.
Having done this, you will have to re-create this account, as mentioned above. Once the account is created, you will have to restart Microsoft Outlook. This worked for me, and I hope it works for you too. These suggestions can also be useful to you if you see Problem connecting to Server message in Outlook.
How do I reconnect my Outlook email?
To reconnect your Outlook email in the Outlook app, you need to create a new profile first. Otherwise, it will continue using the same old profile with which you were having problems. Following that, you can use the default way to add your Outlook email address in the Outlook email app on your computer. For your information, you must insert your email address and password to get started.
How do I sync Outlook with Outlook.com?
To synchronize Outlook with Outlook.com, you must add the @outlook.com or @hotmail.com email address first. For that, you can open the Outlook app and enter your name, email address, and password. Once you click the Next button, the app will fetch your account and show it on your screen almost instantly. You may be required to do this only if you are using Outlook 2016 or Outlook 2013 to access your Outlook.com accounts. You do not have to reconnect to your other email accounts, such as Office 365, Exchange, etc. If you face issues, See this post if you face issues, Troubleshoot issues after reconnecting Microsoft Outlook client to Outlook.com.
