'vê se te serve:
'Em um form:
Option Explicit
Private Declare Function ShellExecute Lib "shell32.dll" Alias "ShellExecuteA" _
(ByVal hWnd As Long, ByVal lpOperation As String, _
ByVal lpFile As String, ByVal lpParameters As String, _
ByVal lpDirectory As String, ByVal nShowCmd As Long) As Long
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Private Sub Command1_Click()
Dim zip_file As String, Ret As Long
zip_file = App.Path & "
nomedoseuarquivo.zip"
ShellExecute Me.hWnd, "Open", _
"
mailto:teste@ig.com.br?subject=" & zip_file & "&body=Zip File Attached", _
vbNullString, vbNullString, vbNormalFocus
While Ret = 0
DoEvents
Ret = FindWindow(vbNullString, zip_file)
Wend
SendKeys "%ia" & zip_file & "{TAB}{TAB}{ENTER}"
End Sub