Using Postman get 500 Internal error sending payload - rest

Question

I am trying to reverse engineer an api request to a server that I don't control. Initially I view the following url (which doesn't require any credentials to logon):
https://www.abc.ca.gov/datport/lqs.html?rpttype=3&rptdateoffset=0
Using Chrome dev tool I see the data is displayed via the following url:
https://www.abc.ca.gov/LQSService.svc/LicenseRequest
I use this url in Postman as a POST request:
POST https://www.abc.ca.gov/LQSService.svc/LicenseRequest
Chrome tools shows the Request Payload which I use in the Body (raw) of the Postman request:
{"data":"<ROOT><PAGENUMBER>1</PAGENUMBER><RPTTYPE>3</RPTTYPE><RPTDATEOFFSET>0</RPTDATEOFFSET><RPTDATE>11/29/2017</RPTDATE><FORMATEDDATE>Wednesday, Nov 29, 2017</FORMATEDDATE><RPTGROUP>DAILY3</RPTGROUP></ROOT>"}
When I execute the request in Postman I get the following error:
{
"ExceptionDetail": null,
"ExceptionType": null,
"Message": "The server was unable to process the request due to an internal error. For more information about the error, either turn on IncludeExceptionDetailInFaults (either from ServiceBehaviorAttribute or from the <serviceDebug> configuration behavior) on the server in order to send the exception information back to the client, or turn on tracing as per the Microsoft .NET Framework SDK documentation and inspect the server trace logs.",
"StackTrace": null
}
The Headers from the results show:
jsonerror →true
Chrome Request Headers also shows the following which I added to the Postman request (Headers) with the same error happening:
X-Requested-With:XMLHttpRequest
Cookie:ASPSESSIONIDCWQRCBDR=IBNIPHCCIGMJLKOPDMDJKCPJ
I also added the following Cookie in Postman as well:
ASPSESSIONIDCWQRCBDR=IBNIPHCCIGMJLKOPDMDJKCPJ; path=/; domain=.www.abc.ca.gov; Expires=Tue, 19 Jan 2038 03:14:07 GMT;
What else may I be missing or not specifying correctly in the Postman request?
The complete Request Headers as shown in Chrome are:
Accept:application/json, text/javascript, */*; q=0.01
Accept-Encoding:gzip, deflate, br
Accept-Language:en-US,en;q=0.9
Connection:keep-alive
Content-Length:210
Content-Type:application/json; charset=UTF-8
Cookie:ASPSESSIONIDCWQRCBDR=IBNIPHCCIGMJLKOPDMDJKCPJ; __utmt=1;
__utma=158387685.1745889465.1508735899.1512200444.1512230785.12;
__utmb=158387685.6.10.1512230783; __utmc=158387684;
__utmz=158387685.1512185091.8.2.utmcsr=google|utmccn=
(organic)|utmcmd=organic|utmctr=(not%20provided)
Host:www.abc.ca.gov
Origin:https://www.abc.ca.gov
Referer:https://www.abc.ca.gov/datport/lqs.html?
rpttype=3&rptdateoffset=0
User-Agent:Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.94 Safari/537.36
X-Requested-With:XMLHttpRequest

Answer 1

Turns out I only needed to specify Content-Type in header.