Office 2003 Disables Search in Office 2007
I accidentally installed Visio 2003 on my corporate pc - because the title on the disc just says "Visio for Enterprise Architects", and doesn't list a version. And it seems, and I can confirm, that if you install an Office 2003 application on your Vista-Office 2007 pc, search stops working in Outlook. Outlook will act like it is searching, and it will do it forever, but it will never find anything.
Oh well. Uninstalled the offending app, and all returned to normal...