Back then, you couldn't just toggle a switch in Settings. If you bought Office in the US or the UK, you got English. If you wanted to type καλημέρα without a red squiggly line underneath, you needed that specific add-on.
But today? Don't risk your hard drive for a spell checker. The cloud speaks Greek now without the piracy. Microsoft Office 2007 Greek Language Pack .rar
Why 2007? Why Greek? And why on earth is everyone looking for a .rar file of it? Back then, you couldn't just toggle a switch in Settings