Configure Outlook to access Office 365 mailbox using IMAP and SMTP

In the following article, we will review how to configure Outlook mail client to connect “Office 365 mailbox” that is hosted on the Exchange Online server by using the IMAP and the SMTP protocol. Generally speaking, Exchange Online provides a variety of methods and protocol, which we can use for connecting to a particular mailbox. Regarding Outlook mail client, the preferred mail protocol is Outlook anywhere (RPC over HTTPS) with a combination of the Autodiscover service which enables Outlook automatically to locate the Exchange Online mail server and the required configuration settings.

Scenario

In a scenario in which we prefer to connect our Outlook mail client using the “good old” Internet mail protocol – IMAP for receiving incoming mail and SMTP for sending Outlook going mail, we will need to use the following configuration settings:

The information about the required protocols and port number appears in Office 365 OWA mail client settings and in addition in the following article-

Outlook settings for POP and IMAP access for Office 365 for business or Microsoft Exchange accounts

Note – the article includes different configuration setting regarding the IMAP protocol, the settings that I manage to use are the setting that appears in the appear in Office 365 OWA mail client settings

To view the information about the IMAP and SMTP protocol, log into your OWA mail client.

• Choose the settings icon
• Select the options menu

• On the left menu bar, select the menu – POP and IMAP

In the following screenshot, we can see the information about the configuration setting of the IMAP and the SMTP protocol.

Creating a new Outlook mail profile – Configure Outlook to access Office 365 mailbox using IMAP and SMTP

As mentioned, when we use the option of IMAP and SMTP protocol, we cannot Take advantage of the Outlook Autodiscover service, which is used to configure for us the required configuration settings. Instead, we will need to configure Outlook mail client by using manual settings.

In the current article, we will demonstrate the required configuration setting for IMAP\SMTP protocol using an Outlook 2016 mail client, but the configuration settings are almost identical to previous versions of Outlook mail client.

• Go to the control panel
• Choose the icon – Mail (Microsoft Outlook 2016) (32 bit)

• Select the option – Show Profiles…

• Select the option – Add…

• In the profile name text box – write the name of the Outlook profile and click OK

• Select the option – Manual setup or additional server types
• Click the Next > button

• Select the option – POP or IMAP

• In the user information section, write your name and your E-mail address (number 1,2)
• In the server information section, in the Account type, select IMAP (number 3)

Now, we will need to provide the hostname (FQDN) of the Office 365 mail server that we need to connect.

• In the section – Incoming mail server, add the server name – outlook.office365.com (number 4)
• In the section – Outgoing mail server (SMTP), add the server name – smtp.office365.com (number 5)
• In the section Logon information, write down your credentials – your Office 365 login name + password (number 6 + 7)

In Office 365 based environment the “login name” described as UPN (user principal name) and the login name is written as an E-mail address.

• Click on the More Settings… option

• Choose the Outgoing Server TAB
• Select the option – My outgoing server (SMTP) requires authentication
• Leave the default settings – Use same settings as my incoming mail server

• Choose the Advanced TAB

In the following tab, we will need to configure the specific settings that are relevant to Office 365 based environment (Exchange Online).

IMAP mail protocol settings

• In the incoming server (IMAP) type the protocol number 993 (number 1)
• In the section – use the following type of encrypted connection, select – SSL (number 2)

SMTP mail protocol settings

• In the outgoing server (SMTP) type the protocol number 587 (number 3)
• In the section – use the following type of encrypted connection, select – TLS (number 4)

• On the bottom of the window, click the Next> button

Outlook client will automatically start a communication test to verify is he can access the mail server based upon the setting that we have provided.

In the following screenshot, we can see that the communication test completes successfully.

• On the bottom of the window, click on the Finish button

In the following screenshot, we can see that the “test e-mail” that was sent by Outlook to the user mailbox.