How can I call up MessageBox?

How can I call up MessageBox?

I drilled down SUPERVISOR750 demo project.

And I meet the screen type - "MessageBox".

How can I call up the MessgeBox screen.

The help says to me.

> No screen switching can be configured in the screen.
> The message box screen must not be called up by means of a screen switching function.

Thanks your any suggestions.


This is a migrated post! Originally posted on 07.04.2017 by user monad. Please be aware that information can be outdated.