WSO2 ESB 4.6.0 does not support the HTTP endpoint feature as 4.7.0. But we can send a HTTP GET request with query parameters using the property REST_URL_POSTFIX in ESB 4.6.0. Below proxy configuration in 4.6.0 will send a GET request with the query parameters defined in REST_URL_POSTFIX. <proxy xmlns=" http://ws.apache.org/ns/synapse " name="myProxy" transports="https,http" statistics="disable" trace="disable" startOnLoad="true"> <target> <inSequence> <property name="uri.var.site" value="33" scope="default" type="STRING"/> <property xmlns:ns=" http://org.apache.synapse/xsd " name="REST_URL_POSTFIX" expression="fn:concat('?site=', get-property('uri.var.site'), '&cm_user_pw=' ,12345 , '&account=' , 'accout' , '&key=' , 'test