Hello Colby!
it can be hard to diagnose this problem with this information but generally speaking the error is a result of trying to install the incorrect version (including not getting the correct 32bit/64bit version). Could you tell her to try a clean install making sure that she has downloaded the version appropriate for her outlook?
https://community.marketo.com/MarketoArticle?id=kA050000000KywLCAS
If this fails, please advise her to contact support who will be happy to help her!