Office 2007

I had to write a marketing paper and was having problems with inserting page numbers in Microsoft Office Word 2007. I had the Beta installed prior to receiving the final version from Microsoft and that appears to be the culprit.
If you're having problems with Office 2007, here is what you need to do:

Start -> Run
Type: %appdata%\Microsoft\Document Building Blocks

You'll find a folder called 1033, go into that folder and delete the file called Building Blocks.dotx.

Restart Word 2007 and the file will be rebuilt properly, which will allow for the galleries of different page number formats to be displayed.