One way:
First write down the path to Outlook.exe. A default path is: C:\Program
Files\Microsoft Office\Office 12\outlook.exe. If you choose to install
Office 2007 to other than the "C" drive, change the drive letter to the
drive you used. I would go to that location and verify that you find
outlook.exe.
Open Start, All Programs. Look for Startup entry. Right click on Startup and
select Explore All Users. When the explore window opens click on File {top
left} and select New, Shortcut. A wizard will open to create a shortcut in
the Startup folder for all users. Enter the full path to outlook.exe in the
text box. Click on Next button and follow directions. Note: this will
place a shortcut to Outlook 2007 in the startup folder for all users of your
computer. If you have your computer configured for multiple users and only
one users wants Outlook 2007 to start at boot, choose Explore when you right
click on Startup {above}. Then a shortcut to Outlook 2007 will be created
only in the startup folder for the current user. If this note confuses you,
ignore it and just create a shortcut to Outlook 2007 in the startup folder
for all users.
Don