Not able to hit the web service on form load, though my code for calling the web service is executed for every time on form load of MFD Ricoh

Hi Every one  
  
I need to call a web service in Form_onload(Form) and web response is stored in an xml file in local path.  
  
Note :- this Script is written in Form_onload(Form) event and check box for "Run on form load" is checked.  
  
  
Issue  
  
I am able to see in my log that my code for calling the web service is executed every time on form load. but on other hand it is not hitting the web service every time it is being called.  
  
i.e It is hitting for the first time when i restarted my NSI Autostore only and for the rest of calls it is not hitting the web server.  
  
Could u please help me out that for every call in form load, it has to hit the NSi Autostore with out restarting my nsi server.  
  
Note:- this web service call is for loading the fields whose type is StringList on the form fileds  
  
  
Thanks  
Chiranjeevi Yadav  
DST Systems  
DST worldWide services  
India.