Failed to Add Exchange Organization - 401 Unauthorized Error

Rowan

I am encountering a "401 Unauthorized" error when trying to add an Exchange organization to our backup/management system. The operation fails during the environment check.

Error log
• Page error log when adding: Failed to add organization, organization: "intemal.com', error parameter: 'check ews api error byclient:172.18.20.21.microsoft.exchange,webservices,data,core,exception,seryiceremote,ServiceReguestException: Threguest failed. The request failed, The remote server returned an error: (401)Unauthorized',[#600001lFailed to check the M365 organization environment
• Client m365_proxy error log: handle get Exchange server inbox mailfolder failed: microsoft ,exchange,webservices,data,core,exception,service,remote,SeryiceReauestException: Thereguest failed, The reguest failed, The remote server returned an error: (401)Unauthorized.

The error seems to occur when the system tries to connect to the Exchange Web Services (EWS) API to validate the environment.

Has anyone seen this before? Any guidance on what might be causing the authentication failure would be greatly appreciated.

Iris Li

Hi, Rowan
Since the administrator account used for the initial addition did not have the ApplicationImpersonation role, this permission needs to be granted before adding the role.

In Exchange Central Administration - Administrator Roles, add an ApplicationImpersonation role.

Rowan

Iris Li Thanks a lot.