Setup error during installation of MS Outlook 2007

We're currently running Windows Mail, but now we want to install Outlook 2007. We don’t have an older copy of Outlook.
Upon installation, I received the following error:
Microsoft Office Outlook 2007 encountered an error during setup.
There was no error code. Also, the installer is from a freshly bought copy of Office 2007 and subsequently Outlook 2007. Previously, I read about threads that suggested an older copy of Outlook, but I don't have one. My operating system is Vista.
I have no idea about this. Suggestions will be accepted cordially. Thanks a lot.
