Unparsable request content

Your HTTP request specifies that the Content-Length of the POST body is 1334652 bytes

POST /TransmittalList.aspx HTTP/1.1  
Host: ccvvv  
Connection: keep-alive
Content-Length: 1334652
...

The actual length of the POST body is only 1163264 bytes (as determined by the HTTP parser seeing two Carriage return/Line feed combinations in the datastream)

\r\n\r\n

This is an HTTP violation, and there is something incorrect (either the calculation of the Content-Length header, or in the body of the POST).