IMPORTANT - this article is for reference purposes. If you are looking to make this kind of change, we recommend speaking to your representative at The Layer.
The Layer supports two methods of Office 365 authentication methods - basic, and the newer modern / OAuth model.
This can be viewed and changed from Settings - Company Setup via the Mail tab.
Once OAuth Authentication has been selected, a field will be present that lets you determine the OAuth Endpoint.
For Office 365, the endpoint will be https://outlook.office365.com/EWS/Exchange.asmx.
If you use your own Exchange server, this will be unique to your organisation.
Logging your EWS impersonation account with OAuth
Click here for information on logging your EWS account in with OAuth.