The story of a machine with a pirated OS and other software is now an old one.
To get it all fixed up, start over. Wipe the drive, install your OS and then your Office. The only glitch can be if your Office license count doesn't support this many installs.
Sorry to read this story again.
I recently purchased a used IBM desktop with XP Pro pre-installed, with a valid COA on the back to use for a media server. As a "bonus" it also came with Office 2007. When I tried to validate the office 2007, MS informed me the serial number was a pirated number, and I needed to buy the real deal. But, as I do not like 2007 anyways and I rarely use Office on this machine, I immediately uninstalled it and installed my genuine copy of Office 2003 Pro.
The problem: I still cannot validate even my GENUINE edition of office 2003 Pro! The error says this serial is a pirated number for an enterprise edition of Office. But I have the real deal discs! And it works fine on my laptop that didn't previously have a pirated version of office 2007 on it. What to do? MS insists they are illegal copies and wants me to send them to them (like I'd trust them to get them back) and IF they are genuine discs, they will replace them with office 2007 home, which I don't want anyway.
Does anyone have a similar problem, and hopefully a fix? This all started because an unscrupulous dealer on eBay sold me a PC with pirated software...