Office 2010 Upgrade, 32 or 64 bit?

Office 2010 is the first release of Office that contains 64 bit edition. It’s recommended to install the 32 bit version Office 2010 due to compatibility issues however if you still want to try 64 bit version keep these in mind.

• 32 bit version works on both 32 bit and 64 bit windows operation systems. But 64 bit version Office 2010 must be installed on 64 bit windows operation systems.
• You can’t upgrade from 32 bit Office 2007 to 64 bit Office 2010 directly, you have to uninstall existing 32 bit Office products prior to install 64 bit Office 2010. (It’s okay to upgrade Office 2007 to 32 bit Office 2010 on either 32 bit or 64 bit operation systems)
• You can’t run 64bit and 32bit office products side by side. For example, you can’t have side by side installation of 32 bit OneNote 2010 and 64 bit Outlook 2010
• Some of 32bit Office Add-Ins might not work on 64 bit Office 2010.