If form's border is set to 0 (none) but ShowInTaskbar is True - icon will not appear unless you do something like the following:
VB Code:
  1. Option Explicit
  2.  
  3. Private Const GWL_STYLE = (-16)
  4. Private Const WS_SYSMENU = &H80000
  5. Private Const WS_MINIMIZEBOX = &H20000
  6.  
  7. Private Declare Function GetWindowLong Lib "user32" _
  8.     Alias "GetWindowLongA" _
  9.     (ByVal hwnd As Long, ByVal nIndex As Long) As Long
  10. Private Declare Function SetWindowLong Lib "user32" _
  11.     Alias "SetWindowLongA" _
  12.     (ByVal hwnd As Long, ByVal nIndex As Long, _
  13.      ByVal dwNewLong As Long) As Long
  14.  
  15. Private Sub Form_Load()
  16. Dim lStyle As Long
  17.  
  18.     'ensure taskbar icon visibility
  19.     lStyle = GetWindowLong(Me.hwnd, GWL_STYLE) Or WS_SYSMENU Or WS_MINIMIZEBOX
  20.     SetWindowLong Me.hwnd, GWL_STYLE, lStyle
  21.    
  22. End Sub