returns xml fragment.
<response success="true" error="">
if success attribute is "true", the document types has been returned successfully like the sample below.
if success attribute is "false", the error attribute indicates the encountered error.
<response success="true" error="">
<DocumentTypes>
<DocumentType TypeID="10101" TypeName="Incoming Fax" PropertySetID="11926" PropertySetName="INCOMINGFAX"/>
<DocumentType TypeID="1015" TypeName="Incoming Letter" PropertySetID="11927" PropertySetName="LETTER"/>
<DocumentType TypeID="10271" TypeName="infoRouter Video" PropertySetID="11928" PropertySetName="VIDEO"/>
<DocumentType TypeID="1014" TypeName="Invoice" PropertySetID="1015" PropertySetName="INVOICE"/>
</DocumentTypes>
</response>