Salesforce is implementing security changes that are going to impact Salesforce orgs including Elements clients starting this month.
This article includes the impact and what steps to taketo prepare before they're enforced.

Clients will need to implement and use Microsoft Graph to connect between Salesforce and Exchange Online. To learn more about this and what is required, click here.
Clients will need to implement domain verification. To learn more about this and what is required, click here.