I've found that after expiration of Office 2010 beta when I want to install trial, installation always ends up with an error 25400, even if everything is uninstalled. I've read that it's because Office refuses to install a trial after using a key that expires (like beta one). If so, is there a solution to reset that? I really need that trial. Please note that I don't want do anything illegal - I just want to use my obtained trial after betatesting Office 2010 before.