Probably because Office knows the difference between an OEM copy and one
that was downloaded from Microsoft as well as the different versions (Small
Business, Pro, etc)

--

JoAnn Paules
MVP Microsoft [Publisher]
Tech Editor for "Microsoft Publisher 2007 For Dummies"


"CS" wrote in message
...
Office 2007 Small Business came preinstalled on my computer. I did not
recieve disks - just the product key. I am having issues with Word, Excel
and Outlook, so I removed Office and installed the trial version. Now, I
cannot activate the trial version using my product key.

Why?

p.s. I installed Office on a second machine using the product key, which
makes a total of two installations.