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Joshua Widup's avatar
Joshua Widup
Brass Contributor
Jan 18, 2017

S4B Mac ADFS failing

Hey everybody - after the most recent updates the client won't log in properly. We are running Office 365 with ADFS as the login provider. The client attempts the login and then passes back what looks...
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Joshua Widup's avatar
Joshua Widup
Brass Contributor
Apr 19, 2017

Sorry to say that it hasn't been fixed...I haven't had the time to chase it with support either.

David Howell's avatar
David Howell
Copper Contributor
Apr 25, 2017

Hi,

We had an issue with S4B on Max OS not signing in. The user experience was a white login box appearing and then nothing else. No errors.

Tried updating Office and installing the March 2017 update for Skype.

 

Environment is ADFS on Server 2016 with IWA and Forms Based Authentication enabled.

Modern Authentication enabled in both Exchange Online and Skype for Business and no users have MFA enabled.

 

I think what broke it was adding the User Agent String 'Mozilla/5.0' to my ADFS WIASupportedUserAgents property

 

The value wasn't detailed enough to cope with non Windows clients and was therefore expecting IWA from the Macs.

 

Amending the value to 'Mozilla/5.0 (Windows NT)' maintains IWA for Windows platform and FBA for non Windows which resolved the issue.

 

There are plenty of other variables which could be at play with this issue but this sorted it for me.

The clincher was this excellent article on ADFS, IWA and FBA found here

 

https://blog.msresource.net/2015/12/11/ad-fs-enhanced-protection-for-authentication-epa-chrome-and-integrated-windows-authentication-iwa/

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