Sending Emails with attachment of less than 10 MB from AWS SES

Question

We are using AWS SES to send Emails from our C# application. We have an attachment(PDF File) of size 9.28MB and when we try to send the Email with the attachment, it throws the following exception:

System.Xml.XmlException: Root element is missing. at System.Xml.XmlTextReaderImpl.Throw(Exception e) at System.Xml.XmlTextReaderImpl.ParseDocumentContent() at Amazon.Runtime.Internal.Transform.UnmarshallerContext.Read() at Amazon.Runtime.Internal.Transform.ErrorResponseUnmarshaller.Unmarshall(UnmarshallerContext context) at Amazon.SimpleEmail.Model.Transform.SendRawEmailResponseUnmarshaller.UnmarshallException(UnmarshallerContext context, Exception innerException, HttpStatusCode statusCode) at Amazon.Runtime.AmazonWebServiceClient.processWebException[X,Y](String requestName, WebException we, HttpWebRequest webRequest, IResponseUnmarshaller`2 unmarshaller, IRequest`1 request, Int32 retries) at Amazon.Runtime.AmazonWebServiceClient.Invoke[X,Y](IRequest`1 request, AbstractAWSSigner signer, IResponseUnmarshaller`2 unmarshaller) at Amazon.SimpleEmail.AmazonSimpleEmailServiceClient.SendRawEmail(SendRawEmailRequest sendRawEmailRequest) at MyApp.AmazonSESWrapper.SendRawEmail(String awsAccessKey, String awsSecretKey, List`1 to, List`1 cc, List`1 bcc, String senderEmailAddress, String replyToEmailAddress, String subject, String body, String text, String filePath, String exceptionDetails)

But when we send a 7.50MB word document as attachment, we are getting the following exception:

Amazon.SimpleEmail.AmazonSimpleEmailServiceException: Message length is more than 10485760 bytes long: '10788624'. ---> System.Net.WebException: The remote server returned an error: (400) Bad Request. at System.Net.HttpWebRequest.GetResponse() at Amazon.Runtime.AmazonWebServiceClient.Invoke[X,Y](IRequest`1 request, AbstractAWSSigner signer, IResponseUnmarshaller`2 unmarshaller) --- End of inner exception stack trace --- at Amazon.Runtime.AmazonWebServiceClient.processWebException[X,Y](String requestName, WebException we, HttpWebRequest webRequest, IResponseUnmarshaller`2 unmarshaller, IRequest`1 request, Int32 retries) at Amazon.Runtime.AmazonWebServiceClient.Invoke[X,Y](IRequest`1 request, AbstractAWSSigner signer, IResponseUnmarshaller`2 unmarshaller) at Amazon.SimpleEmail.AmazonSimpleEmailServiceClient.SendRawEmail(SendRawEmailRequest sendRawEmailRequest) at 

From the Discussion Forum and FAQ, it says the maximum attachment size is 10MB, but the error occurs for less than 10MB attachments also.

https://forums.aws.amazon.com/thread.jspa?messageID=346305

http://aws.amazon.com/ses/faqs/#49

Please suggest on this.

Answer 1

There is also overall message size limit, which is also 10M. As per http://aws.amazon.com/ses/faqs/:

Amazon SES will accept email messages up to 10 MB in size. This includes any attachments that are part of the message.

So you have to ensure your request fits in these limits.

(I personally think its a bug that Amazon API throws "XmlException: Root element is missing." in case when the message size considerably exceeded the limit. It's totally misleading.)