Outlook 2013 SP1 (with latest fixes) and later will be required to connect to Microsoft 365 services

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Microsoft Outlook

Microsoft Outlook

Microsoft today published a blog post to remind users about the upcoming minimum version requirements for connecting Outlook for Windows to Office 365/Microsoft 365 services. From November 1, 2021, only Outlook 2013 Service Pack 1 (with latest fixes) and later will be able to connect to Microsoft 365 services. After this date, several popular versions of Outlook including Outlook 2007, 2010, and Office 2013 versions earlier than 15.0.4971.1000 will not be able to connect with Microsoft 365/Office 365 services.

Microsoft is blocking older versions of Outlook because of the following:

  • Support for basic authentication is ending to increase the security of Microsoft 365 by relying on modern authentication protocols, which are not only more secure, but also provide compliance and policy controls to help you manage your data.
  • We’re working on adding support for HTTP/2 in Microsoft 365. HTTP/2 is a full duplex protocol, which decreases latency through header compression and request multiplexing. On the service side, we’ll be able to better prioritize requests and more effectively push data to clients.

You can learn more about this announcement from the source link below.

Source: Microsoft

More about the topics: microsoft, Microsoft 365, outlook