>Two ways:
>1. Do not allow application to be closed until updates are finished.
>
>2. Have a loader application then when price updates start raise some flag.
>If the user closes the application loader application seek for this flag and if it is raised restart application.

This is a very good idea. Being a Loader an EXE that just fires the real EXE application and seats waiting the app termination, can check with a timer if there is any update and close the main application and itself.

Nice.