How can I see a list of all users who access Exchange via the Outlook Web Access (OWA)?

[Zhdl_Khsro]

How can I see a list of all users who access Exchange via the Outlook Web Access (OWA)?

[#2]

Have you checked the Email app usage report in the portal? https://portal.office.com/adminportal/home#/reportsUsage/EmailClients

[#3]

Thanks a lot, I cannot login to the portal but I used log parser and I got what I want exactly.