You need to dim "i" outside of the timer event, then send one item each time the timer fires, then increment "i" after the "send" happens.

For example:

Code:
Option Explicit

Dim i As Integer

Private Sub Timer1_Timer()
    sock.SendIM List2.List(i), "yep", False
    i = i + 1
    'also, check at this point to see if i is > than list2.listcount-1
End Sub