Exchange Online Microsoft Business Productivity Online Dedicated Microsoft Business Productivity Online Suite Federal More. Less This article describes the various kinds of mailbox permissions that can be granted and how those permissions are granted in Microsoft Exchange Online and in Microsoft Outlook in Microsoft Office 365 dedicated/ITAR. Collaborate for free with online versions of Microsoft Word, PowerPoint, Excel, and OneNote. Save documents, spreadsheets, and presentations online, in OneDrive. Message tracking in Office 365 (Exchange Online) Message tracing or message tracking in office 365 is one of the common tools used by the administrators to monitor the email flow direction. When emails travel through office 365, some of the information about them put away in logs and accessible for regulatory purposes. By default, POP3 and IMAP4 are enabled for all users in Exchange Online. To enable or disable POP3 and IMAP4 for individual users, see Enable or Disable POP3 or IMAP4 access for a user. To customize the POP3 or IMAP4 settings for a user, see Set POP3 or IMAP4 settings for a user.

As of October 13, 2020, only these versions of Office are supported for connecting to Office 365 (and Microsoft 365) services:

• Microsoft 365 Apps for enterprise (previously named Office 365 ProPlus)
• Microsoft 365 Apps for business (previously named Office 365 Business)
• Office 2019, such as Office Professional Plus 2019
• Office 2016, such as Office Standard 2016

Examples of Office 365 services include Exchange Online, SharePoint Online, and OneDrive for Business.

For Microsoft 365 Apps, you must be using a supported version. For a list of which versions are currently supported, see Update history for Microsoft 365 Apps.

Important

We won’t take any active measures to block other versions of the Office client, such as Office 2013, from connecting to Office 365 services, but these older clients may encounter performance or reliability issues over time.

Impact of using older Office clients to connect to Office 365 services

After October 13, 2020, ongoing investments to our cloud services will not take into account older Office clients. Over time, these Office clients may encounter performance or reliability issues. Organizations that use these older clients will almost certainly face an increased security risk and may find themselves out of compliance depending upon specific regional or industry requirements.

Office 365 Exchange Online App

Therefore, administrators should update older Office clients to versions of Office supported for connecting to Office 365 services.

Upgrade resources available to administrators

We recommend that you upgrade older Office clients to a subscription version of the Office client, such as Microsoft 365 Apps for enterprise. The most up-to-date subscription versions of the Office client are always supported connecting to Office 365 services.

We provide various services to help you upgrade to subscription versions of the Office client. The following list provides some examples of resources that are available:

• Microsoft FastTrack, for migration and deployment assistance from Microsoft experts.
• App Assure, for assistance from Microsoft with application compatibility issues.
• Deployment guide for Microsoft 365 Apps, for technical documentation.
• Product lifecycle dashboard and upgrade readiness dashboard, for users of Microsoft Endpoint Configuration Manager (current branch).
• Readiness Toolkit for Office add-ins and VBA, to help identify potential issues with add-ins and VBA macros used in your organization.

Upcoming changes related to connectivity to Office 365 services

Retirement of TLS 1.0 and 1.1

After October 15, 2020, you must be using at least TLS 1.2 to connect to Office 365 services. For more information, see TLS 1.0 and 1.1 deprecation for Office 365 and Preparing for TLS 1.2 in Office 365 and Office 365 GCC.

Basic authentication with Exchange Online

There are some changes planned related to the use of Basic Authentication with Exchange Online. For more information, see Basic Authentication and Exchange Online – February 2021 Update.

Retirement of Skype for Business Online

Skype for Business Online will be retired on July 31, 2021. For more information, see Skype for Business Online retirement.

Minimum version requirements for Outlook for Windows

Office 365 Exchange Online Plan 1

Note

The information in this section was communicated in the following Message center post in the Microsoft 365 admin center.

• Message ID: MC229143
• Message title: Update to Microsoft 365 and Outlook for Windows connectivity
• Publish date: December 9, 2020.

Starting on November 1, 2021, the following versions are the minimum versions of Outlook for Windows you need to be using to be able to connect to Microsoft 365 services, such as Exchange Online.

• Version 1706 of Microsoft 365 Apps
• Version 16.0.4600.1000 of Office 2016 (with the November 2017 Update, KB 4051890)
• Version 15.0.4971.1000 of Office 2013 (Service Pack 1 with the October 2017 Update, KB 4043461)

All versions of Outlook 2019 should be able to connect to Microsoft 365 services, but only the most current version is supported.

Even though newer versions of Outlook 2013 might be able to connect to Microsoft 365 services, it's not supported and you may encounter performance or reliability issues.

Versions of Outlook that are newer than those listed, but aren't the most current (supported) versions, may experience connectivity issues. To find what is the most current (supported) version, see the following articles:

Office 365 Exchange Online Price

Additional information about connectivity to Office 365 services

Office 365 Exchange Online Plan 2

• Versions of Office 2019 and Office 2016 will be supported for connecting to Office 365 (and Microsoft 365) services until October 2023.
• Connecting to Office 365 services using Office 2016 for Mac isn’t supported. That’s because Office 2016 for Mac reached its end of support on October 13, 2020.
• This information about connecting to Office 365 services also applies to Project and Visio.
• This information about connecting to Office 365 services does not apply to InfoPath 2013 or SharePoint Designer 2013.
• For end of support dates for different versions of Office on various versions of Windows, see the Office configuration support matrix.
• To discuss or learn more about end of support for Office versions, visit Microsoft Office End of Support on the Microsoft Tech Community.