I'm trying to install a trial version of Microsoft office 2010 on my Vista computer. My question is that there is a previous version of it on this machine that i'm using that was used and wont install the new trial version. Can I delete the old version? By deleting the previous version will the deletion of the first version also delete all or any files, or documents made with the previous version? If so is there any way to keep or preserve those files and or documents made?