To override the Content-type in your clients, use the HTTP Accept Header, append  the .xml suffix or  ?format=xml
        
        HTTP + XML
         The following are sample HTTP requests and responses. 
            The placeholders shown need to be replaced with actual values.
POST /api/contacts/archive HTTP/1.1 
Host: cpo.hostedsuite.com 
Accept: application/xml
Content-Type: application/xml
Content-Length: length
<ArchiveContactsRequest xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/Evo.HostedSuite.Core.ServiceModel">
  <CustomerName>String</CustomerName>
  <Password>String</Password>
  <UserName>String</UserName>
  <ContactId>String</ContactId>
  <ContactPhoneNumber>String</ContactPhoneNumber>
</ArchiveContactsRequest>
 
HTTP/1.1 200 OK
Content-Type: application/xml
Content-Length: length
<DefaultResponse xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/Evo.HostedSuite.Core.ServiceModel" />