MS Office Install Gotcha
This is true for Microsoft Office, and most likely a lot of other applications as well. When installing new versions of an application we need to keep in mind associated plugins/add-ons. Those plugins/add-ons often correspond with specific editions of office, not only the edition such as 2007 and 2010, but also the ‘bitness’ as well. So if you are upgrading from Office 2007 Pro 32-bit to Office 2010 Pro 64-bit, there is a pretty good chance your add-ins won’t work, so just plan for that and be prepared.