An internal server error occurred. The operation failed. connecting to O365 Exchange using

Question

Hello,

We changes the authentication mode from Basic to Oatuh for our EWS exchange service.

Very often I am getting internal server error while connecting to office365 account.
I am not able to understand what is this and why is this happening so frequently.

Cannot access mailbox for service account: Microsoft.Exchange.WebServices.Data.ServiceResponseException: An internal server error occurred. The operation failed.
at Microsoft.Exchange.WebServices.Data.ServiceRequestBase.ProcessWebException(WebException webException) in \REDMOND\EXCHANGE\BUILD\E15\15.00.0913.015\SOURCES\sources\dev\EwsManagedApi\src\EwsManagedApi\Core\Requests\ServiceRequestBase.cs:line 990
at Microsoft.Exchange.WebServices.Data.ServiceRequestBase.GetEwsHttpWebResponse(IEwsHttpWebRequest request) in \REDMOND\EXCHANGE\BUILD\E15\15.00.0913.015\SOURCES\sources\dev\EwsManagedApi\src\EwsManagedApi\Core\Requests\ServiceRequestBase.cs:line 827
at Microsoft.Exchange.WebServices.Data.ServiceRequestBase.ValidateAndEmitRequest(IEwsHttpWebRequest& request) in \REDMOND\EXCHANGE\BUILD\E15\15.00.0913.015\SOURCES\sources\dev\EwsManagedApi\src\EwsManagedApi\Core\Requests\ServiceRequestBase.cs:line 724
at Microsoft.Exchange.WebServices.Data.MultiResponseServiceRequest`1.Execute() in \REDMOND\EXCHANGE\BUILD\E15\15.00.0913.015\SOURCES\sources\dev\EwsManagedApi\src\EwsManagedApi\Core\Requests\MultiResponseServiceRequest.cs:line 157
at Microsoft.Exchange.WebServices.Data.ExchangeService.BindToFolder(FolderId folderId, PropertySet propertySet) in \REDMOND\EXCHANGE\BUILD\E15\15.00.0913.015\SOURCES\sources\dev\EwsManagedApi\src\EwsManagedApi\Core\ExchangeService.cs:line 278
at Microsoft.Exchange.WebServices.Data.ExchangeService.BindToFolderTFolder in \REDMOND\EXCHANGE\BUILD\E15\15.00.0913.015\SOURCES\sources\dev\EwsManagedApi\src\EwsManagedApi\Core\ExchangeService.cs:line 295
at Microsoft.Exchange.WebServices.Data.Folder.Bind(ExchangeService service, WellKnownFolderName name) in \REDMOND\EXCHANGE\BUILD\E15\15.00.0913.015\SOURCES\sources\dev\EwsManagedApi\src\EwsManagedApi\Core\ServiceObjects\Folders\Folder.cs:line 89

Can anyone have any idea about this ?

Answer 1

Hi @Dashore, Nitesh ,
You could try to add a header after setting ImpersonalteUserId service.HttpHeaders.Add("X-AnchorMailbox", mailbox.Mailbox);
Recently it seems that quite a few people have encountered this problem, you may refer to this article:
https://techcommunity.microsoft.com/t5/exchange/ews-with-oauth-quot-an-internal-server-error-occurred-the/m-p/3609047

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Answer 2

Hi @Jame Xu-MSFT

I do nothave any issue in developing the software. my application is working and using EwsManagedApi, i am able to read the emails but only once in a 505 time I get the error what I mentioned above.
This starts happening after the authentication change from basic to OAuth.