[2023.12.04] 11:10:51.184 [10.10.10.10,myuser@mydomain.com,c5b8e1c7-f9d4-4636-af81-339e6380bbc6,eM Client/9.2.2157.0 (ExchangeServicesClient/9.2.2157.0)] 

[2023.12.04] OUT >> req#c5b8e1c7-f9d4-4636-af81-339e6380bbc6 >> (xml:200)

[2023.12.04] <m:CreateItemResponse xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types" xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages">

[2023.12.04]   <m:ResponseMessages>

[2023.12.04]     <m:CreateItemResponseMessage ResponseClass="Error">

[2023.12.04]       <m:MessageText>The user account which was used to submit this request does not have the right to send mail on behalf of the specified sending account. Cannot submit message.</m:MessageText>

[2023.12.04]       <m:ResponseCode>ErrorSendAsDenied</m:ResponseCode>

[2023.12.04]       <m:DescriptiveLinkKey>0</m:DescriptiveLinkKey>

[2023.12.04]       <m:MessageXml />

[2023.12.04]       <m:Items />

[2023.12.04]     </m:CreateItemResponseMessage>

[2023.12.04]   </m:ResponseMessages>

[2023.12.04] </m:CreateItemResponse>