How can I turn Outlook alerts off?

When I try to send an email from my Excel VBA program I get the following
alert.
"A program is trying to automatically send e-mail on your behalf. Do you
want to allow this?"
Yes, No or Cancel.

Is there a way to either turn off the alert or automatically answer Yes.

Relevent part of program:
---------------------------------------------
Set appOL = CreateObject("Outlook.Application")
Set appMess = appOL.CreateItem(olMailItem)

For cnt = 1 To 99
If ISLIKE(Cells(cnt, 12).Value, "*@*") Then 'does cell contain email
address?
appMess.To = "Valid.e-mail@address"
appMess.Subject = "tester"
appMess.Body = "test"
appMess.Send ------ this causes alert to show

End If
Next cnt

appMess.Quit
appOL.Quit
Set appOL = Nothing
Set appMess = Nothing

---------------------------

Henry