Word is crashing

Hello,
We use windows vista business, and office 2007.
every time we use style, one lady always uses them, when she selects a few lines and then says restart numbering, the whole work like crashes and restarts.

We have already renamed the data key and recreated it, and we have removed the adobe addin and let it recreate itself too.
this was after all googling, and everyone seemed to have the same prob, and no ones answer helped me.

Can anyone please help me?

Thank you