Office 365 will drop TLS 1.0 and 1.1 Support starting 31st October 2018

Microsoft has announced that as of October 31st ( Moved from the 1st March ) it will be dropping TLS 1.1 Support and only allowing TLS 1.2

https://blogs.technet.microsoft.com/exchange/2018/02/09/an-update-on-office-365-requiring-tls-1-2/

12-22-2017-SSL_Table1-1024x243[1].jpg

What you need to do 

https://support.microsoft.com/en-us/help/4057306/preparing-for-tls-1-2-in-office-365

1 ) Check for 2008 R2 and Windows 7 Devices and make sure this KB is installed : https://support.microsoft.com/en-au/help/3140245/update-to-enable-tls-1-1-and-tls-1-2-as-a-default-secure-protocols-in

Make sure this Reg key is set

https://blogs.technet.microsoft.com/schrimsher/2016/07/08/enabling-tls-1-1-and-1-2-in-outlook-on-windows-7/

2) Make sure you are not using any of these devices which do not support TLS 1.2

  • Android 4.3 and earlier versions
  • Firefox version 5.0 and earlier versions
  • Internet Explorer 8-10 on Windows 7 and earlier versions
  • Internet Explorer 10 on Win Phone 8.0
  • Safari 6.0.4/OS X10.8.4 and earlier versions

3) Check your devices e.g. MFD and Phone Systems support TLS 1.2