In March, a rumor started about there being a 64-bit version of Office 2010 and in April, we got official confirmation from Microsoft that this would indeed be happening. Ever since then, the number one question from readers commenting on Office 2010 posts was whether or not both 32-bit and 64-bit flavors would be available on one DVD. With Vista, this was not possible due to size constraints. However, with Office 2010, readers speculated, it might be possible to pull off.

So far, Microsoft has refused to give me details on whether or not they would be doing this, but with the Office 2010 32-bit and 64-bit leak (build 14.0.4006.1010) over the weekend, speculation is turning into a believable rumor. While trying to install the 64-bit version on my Vista box, I got an error (pictured above), that would suggest Microsoft is indeed trying to put both on the same disc. I've quoted the important text:

If you want to install 64-bit Office 2010, you must uninstall all 32-bit Office products first, and then run setup.exe in the x64 folder. If you want to install 32-bit Office 2010, close this setup. Then navigate to the x86 folder at the root of your CD/DVD and run setup.exe.

Presumably, this would mean that, just like with Vista, the same product key can be used to install the 32-bit or the 64-bit version of the same software. Of course, it is possible that this error is only there for the development phase of the product, but something tells me that Microsoft would rather have one DVD if it was possible. I will continue pestering Microsoft for an official answer to the question and will keep you posted accordingly.