This should do it...
You need to run this code in the workbook_open section
Sub What_day()
If Choose(WeekDay(Now()), "Sunday", "Monday", "Tuesday", "Wednesday",
"Thursday", "Friday", "Saturday") = "Monday" Then
'run macro for Monday
msgbox "today is Monday"
ElseIf Choose(WeekDay(Now()), "Sunday", "Monday", "Tuesday",
"Wednesday",
"Thursday", "Friday", "Saturday") = "Tuesday" Then
'run macro for Tuesday
msgbox "today is Tuesday"
ElseIf Choose(WeekDay(Now()), "Sunday", "Monday", "Tuesday",
"Wednesday",
"Thursday", "Friday", "Saturday") = "Wednesday" Then
'run macro for Wednesday
msgbox "today is Wednesday"
ElseIf Choose(WeekDay(Now()), "Sunday", "Monday", "Tuesday",
"Wednesday",
"Thursday", "Friday", "Saturday") = "Thursday" Then
'run macro for Thursday
msgbox "today is Thursday"
ElseIf Choose(WeekDay(Now()), "Sunday", "Monday", "Tuesday",
"Wednesday",
"Thursday", "Friday", "Saturday") = "Friday" Then
'run macro for Friday
msgbox "today is Friday"
ElseIf Choose(WeekDay(Now()), "Sunday", "Monday", "Tuesday",
"Wednesday",
"Thursday", "Friday", "Saturday") = "Saturday" Then
'run macro for Saturday
msgbox "today is Saturday"
ElseIf Choose(WeekDay(Now()), "Sunday", "Monday", "Tuesday",
"Wednesday",
"Thursday", "Friday", "Saturday") = "Sunday" Then
'run macro for Sunday
msgbox "today is Sunday"
End If
End Sub