As of today, October 31st 2018, TLS 1.0 will no longer be supported by Office 365

First things first:

This does NOT mean that software and devices using TLS 1.0 will suddenly stop working. Currently, Microsoft will not block these connections, and neither an official date is released for disabling/removing TLS 1.0 in Office 365

So, what’s about TLS 1.0 anyway?

TLS 1.0, which stands for Transport Layer Security version 1.0, is being removed from the list of supported protocols within Office 365. This means it’s being replaced with a new minimum requirement of (at least) version 1.2.

By the way, as a best practice, you should always configure your servers and applications to leverage the latest protocol versions to ensure they are using strongest ciphers and algorithms. Also consider to disable TLS 1.0 entirely.

Okay, what impact will this bring to my infrastructure?

You might be affected when you’re using any of the following list:

  • Windows Server 2008 R2 or earlier
  • Windows 7 or earlier
  • Office 2007 or earlier
  • Android 4.3 or earlier
  • Firefox 5.0 or earlier
  • Internet Explorer 8 till 10 on Windows 7 and earlier
  • Internet Explorer 10 on Windows Phone 8.0
  • Safari 6.0.4/OSX 10.8.4 and earlier
  • Lync for Mac 2011
  • Lync 2013 for Mobile (iOS, Android, Windows Phone)
  • Lync “MX”
  • Lync 2010 clients
  • Lync Phone Edition
  • Lync Room System (also known as SRSv1)
  • And maybe more, check your devices and business applications

Microsoft released an article which supports by preparing your infrastructure to support TLS 1.2. Check it out: