Internet Explorer crashes when you try to open an Office document in SharePoint 3.0

Microsoft has made a hotfix available for an issue that might crash your browser when opening a document from a SharePoint 2007 site in Office 2007.

This problem occurs if the following conditions are true, in the order in which they are presented:
• You install a Microsoft Office 2003 product on the computer.
• You install one or more 2007 Office system programs on the computer.
• You repair or update the installation of an Office 2003 product.

http://support.microsoft.com/kb/938888