Microsoft updated the experience for iOS, Android, and Windows Phone 8.1 users who were blocked from accessing Exchange Online using native Exchange ActiveSync email clients because their devices are not enrolled or compliant with policy. When users are blocked, they will receive an email from Exchange with a link to open the Microsoft Intune Company Portal app (iOS and Android) or the Company Portal website (Windows Phone 8.1). The new guided workflow will take users through the steps for enrolling and addressing any compliance issues. This update won’t affect users who already have access to email.
You can read this blog update by Microsoft to Conditional Access for Exchange Online using Microsoft Intune
Previous blog post “Conditional Access for Exchange Online using Microsoft Intune” has now been updated to include the new improved user experience.