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Microsoft Issues Final Warning for Monday, November 1st


Final Notice Given Friday, October 1st


On Friday October 1, Microsoft issued a 30-day notice & final reminder that starting November 1, 2021 older versions of Outlook for Windows (as part of Office and Microsoft 365 Apps) will not be able to connect with Office 365 and Microsoft 365 services. 

How will this affect my company?


Starting November 1, 2021 the following versions of Outlook for Windows (as part of Office and Microsoft 365 Apps) will not be able to connect with Office 365 and Microsoft 365 services such as:


Office and Microsoft 365 Apps   


Office 2013


Office 2016 


Microsoft 365 Apps for enterprise (formerly Office 365 ProPlus)                      
Microsoft 365 Apps for business (formerly Office 365 Business)                   

Outlook for Windows Version

15.0.4970.9999 and older

16.0.4599.9999 and older

1705 and older

1705 and older

Microsoft 365 services won't work with Outlook 2007 and 2010 after November 1, 2021

Only Outlook 2013 Service Pack 1 or later will be supported after this date.

Make sure that your version is supported!

What's Changed?

Microsoft explained that older Outlook 2007 and Outlook 2010 clients will be incompatible with these changes, including an end to support of Basic Authentication — essentially, the long-standard username + password combination.
Microsoft is cutting off support for these older versions of Outlook to improve the security of the service. Microsoft 365 is moving to more modern authentication protocols. These newer protocols are more secure but require up-to-date versions of Outlook.
The other change is that Support for HTTP/2 is being added to Microsoft 365. This lowers latency and has other advantages but also requires newer versions of Outlook.


Microsoft was 'Nice' Last Year


Last October, in a move that tech insiders describe as "surprisingly gracious," Microsoft dropped support for older versions of Office and said even though support would end, it didn't mean connectivity would end. 

"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," the developer said.

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Microsoft: 'Not so Nice' this year!

The November 1, 2021 deadline REALLY WILL cut older Outlook clients from Microsoft's services. (It seems they have no way of keeping connectivity)

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What do I need to do if my current Outlook won’t be supported?

Some Microsoft-provided Upgrade Guidance: 


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Consider a Subscription Model

Microsoft recommends that users switch to the Office 365 or Microsoft 365 subscription model, which provides always up-to-date client software.
November 1st falls upon a Monday!
Make sure you are prepared for that week, not in a bad situation that could have been avoided.

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