One possible way is to set the registry key
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run with a
string value that has the full path and executable for Outlook. So it may
look like this:
Outlook REG_SZ C:\Program Files\Microsoft Office\Office10\OUTLOOK.EXE
Assuming it is installed in the default location and that it is the same for
every machine you apply this too.
Mike.