Every now and then, we face this issue where one or two operations in the webservice which have been working well will stop returning the results after a while. This happens only on the MWS. These operations continue to work in the preview server though.
We are using Designer 7.2. Just to let you know that all possible things (regenerate webservice, bounce Designer, delete project WAR and project folder from MWS and bounce MWS) have been done before posting this message.
If you have seen this behavior, could you please reply back with a resolution (if any).