OAuth Authentication for EWS managed API for o365 and Exchange 2010

Question

we have moved some user mailboxes to o365 but some user and room mailboxes remain on-prem Exchange 2010 servers. Our EWS managed API application is currently using basic authentication with impersonation service account. we are changing it to use OAuth authentication. Will OAuth works in EX2010? can we use OAuth Token from Azure AD When making EWS requests to get room availability details or read user's calendar on- prem? how is impersonation handled in OAuth?

Thanks !

Answer 1

Oauth authenticatin can not be used for EX2010, sadly.

OAuth authentication for EWS is only available in Exchange as part of Office 365. EWS applications require the "Full access to user's mailbox" permission.