The following document outlines information on the ITS officially two-factor supported email clients and community contributions on other clients which may also work.
Supported Software:
Windows: Microsoft Office 2016, 2019, or Office 365 -- NOT: Office 2010, 2013
Mac: Microsoft Office 2016, 2019, or Office 365 -- NOT: Office 2011
Unsupported:
Mac: Apple Mail - requires macOS X 10.14 or higher. Mail on 10.13 or below will not work with DUO. ITS doesn't provide support for Apple Mail.
MS Outlook app, from the device's app store
DUO Mobile app
Android: Use the MS Outlook app. Minimum Android version: Android 7.0 or higher
iPhone, iPad:
Apple Mail requires iOS 11.x+ to run. This is the iPhone 5s, 6, and higher.
Apple Mail will work with two-factor but is not supported.