source : https://msdn.microsoft.com/en-us/library/sfw6660x(v=vs.84).aspx

            http://ss64.com/vb/msgbox.html

Displays a message in a dialog box, waits for the user to click a button, and returns a value indicating which button the user clicked.

Syntax

MsgBox(prompt[, buttons][, title][, helpfile, context])

rep=Msgbox("Reset scrapbook.rdf ?",vbYesNo+vbInformation, numver )

Oui : rep = 6

Non : rep = 7