Update: as of March 2017 everyone is moved to the new server.

Everyone is moved to the new Outlook.com server. If you have the account configured as Exchange ActiveSync (EAS) you need to use autoaccount setup to add the account back; EAS is no longer supported in Outlook and all Outlook.com accounts will need to be added as Microsoft Exchange (you can use IMAP if you only need email support.)

Outlook 2013 & Outlook 2016

Outlook 2013 and Outlook 2016 users shouldn't have any disruption when their account is moved as Exchange ActiveSync (EAS) will continue to sync, however we highly recommend removing the EAS account from Outlook and using auto account setup to add it back. This will create it as an Exchange server account and all features will work, such as adding attachments to appointments, importing mail, and contact groups.

Click on the File tab, then Account Settings button and select Account Settings to open the Account dialog.

Select the Exchange ActiveSync account and click Remove. Then click New to open the Add New Account dialog, where you'll type in your email address and password. Tip: you only need to enter your email address in this dialog, then click Next. Outlook will ask for your password if it's not already saved in the Credential Manager.

Outlook 2010 & Older

If you are using Outlook 2010, Outlook 2007, or Outlook 2003, once the account is moved, the Outlook Connector will stop working, with these send and receive errors:

Task 'poremsky@outlook.com' reported error (0x8004102A) : 'Error with Send/Receive. There was an error synchronizing your folder hierarchy. Error : 80041004.'

Task 'poremsky@outlook.com' reported error (0x8DE00005) : 'There is an error synchronizing your mail account. Please verify your account is configured correctly by first accessing your mail on the web. Error: 3219. Server. An error occurred in looking up the user's information in mserv. '

Mail flow will be restored after deleting the Connector account and using auto account setup to re-add the account to the profile. Outlook 2010 and Outlook 2007 will connect using Exchange while Outlook 2003 will use IMAP.

Because Outlook 2007 doesn't support multiple Exchange accounts in a profile, any users with Outlook.com and an existing Exchange account in the current profile will need to use two profiles going forward (or upgrade to a newer version of Office.)

Unfortunately, Outlook 2003 users will lose calendar and contact sync. These users will need to upgrade to a newer version of Office or use another mail client that supports calendar and contact sync if they want to sync calendar and contacts. Alternatives include the Windows 8 or 10 Mail app or eM client.

Remove Outlook Connector Accounts

After their Outlook.com account is migrated to the new server, users will need to remove the Connector account from their profile. Outlook 2010 and Outlook 2007 users will need to use auto account setup to add it back as an Exchange account while Outlook 2003 users will need to add the account back as IMAP (recommended, but POP3 is an option). Calendar and Contacts will not sync in Outlook 2003.

Outlook 2007 users who also have an Exchange account in their profile will need to use a separate profile for Outlook.com as you cannot have two Exchange accounts in an Outlook 2007 profile. Outlook 2010 and above support multiple Exchange accounts in a profile.

To remove and re-add the account in Outlook 2010 or Outlook 2007:

In Outlook 2010, you can remove the Outlook Connector account from File, Account settings , however, in Outlook 2007, you can't add the new account while Outlook is open and need to close Outlook and open the Control Panel, find Mail then remove the account and add it back. You can use this same method for Outlook 2010 as well.

After opening Mail, click Email Accounts.

Select the Connector account (the account type is MAPI) and click Remove.

If you don't have another email account or a pst in your profile, you'll need to add a pst file or add the Exchange account before removing the old account.

After removing the connector account, click New to open the auto account setup dialog. If using Outlook 2007, you'll need to select Microsoft Exchange, POP3, IMAP, or HTTP on the next screen.

Type your name, email address and password in the fields. After Outlook sets the account up, restart Outlook.

If your Outlook.com account uses a domain name not owned by Microsoft, such as gmail.com, yahoo.com, comcast.net, etc, youll need to add an Outlook.com alias to the account to set it up as Exchange. Instructions are at Add an Alias to an Outlook.com Account

If you use Outlook 2007 and have two Exchange accounts (either Outlook.com or your corporate account), you'll need to use IMAP or POP for one account or use two separate profiles. POP support is not enabled by default, you'll need to change this in Outlook.com. (Instructions are at the end of this article.)

To remove and re-add the account in Outlook 2003:

1. Outlook 2003 users will go to Tools, Email Accounts
   View or Change Existing Accounts then click Next.
   
2. Select the account and click Remove.
   
3. Click Add, then select IMAP and click Next.
4. Type imap-mail.outlook.com for the incoming server name
5. Type smtp-mail.outlook.com for the outgoing server.
   
6. Click More Settings.
7. In the Internet E-mail Settings dialog box, select the Outgoing Server tab and use the following settings:
8. Select My outgoing server (SMTP) requires authentication.
   Select Use same settings as my incoming mail server.
9. Select the Advanced tab.
10. In the Incoming Server (IMAP) section select This server requires an encrypted connection (SSL). This will update the incoming port number automatically, to the correct one.
11. In the Outgoing server (SMTP) section, select This server requires an encrypted connection (SSL). Update March 23 2017: use port 25.
    
12. Click Finish and return to Outlook.

Enable POP3 Support

POP3 support is disabled by default in the new Outlook.com accounts. You can enable it in Outlook.com's Options.

1. Log into Outlook.com using a web browser.
2. Click the Gear icon then choose Options.
3. Find POP and IMAP along the left side
4. Click Yes under Let devices use POP.
   

Uninstall the Outlook Connector

After removing the Outlook Connector account from your profile, you can uninstall the connector in Control panel, Programs and Features .

Add the Account to a Smartphone or Tablet

When you add the account to a smartphone or tablet, choose Exchange as the account type. If asked for a server name, use outlook.office365.com.

This video shows how to do it on an Apple device, but the basic steps are similar for Android devices.