Hi Suki,
Try the troubleshooting links below to help:
http://zone.ni.com/devzone/conceptd.nsf/webmain/D5F8511921D0352586256A330059DEF9?opendocument&node=DZ52188_US
http://digital.ni.com/public.nsf/3efedde4322fef19862567740067f3cc/c2aea878c555e5e186256b2700625b5b?OpenDocument
Be careful of you Internet Explorer security settings when using the web client. They need to allow the ActiveX object to be opened.
Good Luck!
Mike