|Try downloading openoffice.org (free download) and see if it can open it. If it can, you may also be given a few options if you try to resave it (save as) in a more compatible format (I know that Openoffice Writer offers a few versions of Word like Word '97/XP, Word 2003, etc. as well as other text document formats). |
The difference may be in that the one installation of Office may have a compatibility patch installed without you realizing it. This patch may be available on MS Office site and/or through Windows Update under the optional updates.
You have to be a little bit crazy to keep you from going insane.