Hi @ Ardan Zaki ,
For better troubleshooting, I would like to confirm the following points with you:
- What is the current version of Exchange Server? Are multiple servers coexisting?
- What actions were performed before this error occurred?
- Is it normal to log in with EMS? If there is an error, please provide relevant screenshots for us to research together, thank you.
- Please check if there is enough disk space on the server? If so, try restarting the server to see if anything changes.
In addition, can you check the application log when logging in to the ECP and OWA pages, share the error log here, it will help to resolve this issue.
（kindly note:In order to avoid the disclosure of your privacy, please remember to hide your personal information）
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