Alan,
Another way to go about this is to send a message to the Outlook application/window. You could probably go low level with the Win32API which I didn't try, or you could use the Windows Scripting Host SendKeys method to do it too. The following code worked for me by using the menu structure in Outlook to get to the Send/Receive-All Accounts menu item. It's a simplistic approach, but may suit your needs.
IF oOutlook.Application.ActiveExplorer.WindowState = olMinimized
oOutlook.Application.ActiveExplorer.Activate()
ENDIF
oWshShell = CreateObject("WScript.Shell")
WITH oWshShell
.AppActivate("Microsoft Outlook")
.SendKeys("%T")
.SendKeys("E")
.SendKeys("{ENTER}")
ENDWITH
Kendall Webb
Senior Software Engineer
MCAD.Net/MCSD.Net