i think this one might be really easy for more experienced people, but it has me stumped.

I try to add an item to a listbox (list1) using list1.additem

whenever I go to the sub (before it goes through it) it breaks and says "argument not optional"

Code:
Private Sub Calendar1_Click()
'some other file opening code

For i = 1 To datefilelength
    List1.AddItem = events(i).appointments
Next i

End Sub