Microsoft office 2007 install help?

I am trying to install Microsoft office, i have an older version of office and when i install the new Microsoft office that says it doesn’t need a serial cause its pre-activated but it ask for a serial. when i try to open word and any other program
Answer #1
Run removeoga.bat and you’ll be good to go
http://www.fixr.co.uk/2009/10/09/remove-oga-notifier/
Answer #2
Or PM me for a legal key.