What we mentioned in the Enabling two-factor authentication recipe applies also to the mobile apps, but we have to add another mechanism called app password to make it work on these kinds of clients. It is an additional feature required for all the non-browser apps.
Lync and other non-browser apps will require an app password, which we are able to generate using the following screen:
The app password will be shown only once, so remember to save it.
From now on, the app password will replace the account password when the user tries to open one of the multifactor-authentication-enabled apps.
The user is enabled to generate many app passwords (for example, one for every device) and delete them as required. It is required to access the Office 365 portal with the user, select Office 365 settings, go to the Additional Security Verification screen, and select the Update my phone numbers used for account security, as shown in the...