Outlook 2003 on Desktop disappeared

I recently have upgraded some of our users from Office 97 & Outlook 98 & 2000 to Office 2003 Standard Edition. On some of the upgrades, the Outlook program icon is properly replaced on the administrator & user’s desktops, but on some other upgrades it’s not… I have to manually created a shortcut on the desktop myself.

All the PCs are configured identically, so I can’t figure out why this might happen on some but not all computers. Does anyone have an idea why this might occur, and how I can work around the situation?

Any assistance would be greatly appreciated. Thanks in advance.