We're trying to allow vendors to use EWS to connect to mailboxes on O365. We've disabled MFA for this specific user.
When we test connection to the EWS test site https://outlook.office365.com/ews/exchange.asmx internally in the corp network, it works. We get a prompt to enter userUPN and password. When we're trying outside of the corporate network, we get a prompt for userUPN and password. However, we can get through. It times out.
Does anyone know if this is the correct EWS link to test if it's working? Does that authentication come back to the corporate ADFS?
Do you deploy hybrid? Or just sync via AAD connect? Do you deploy ADFS?