title: how to execute a vba macro every 30 minutes automatically?
body: <p>I'm working on a project to send alert notifications to a mailing list. I've an excel file with a vba macro that permit its updating from a datatbase. I need to execute the macro in the file automatically every 30 minutes without having to open the file.
  i've been told to write this macro in a separate program, but i don't know how to do it.</p>