I hope I did not misunderstand your question. IMO, MSO version string and Project’s version string (I mean client) cannot match since products go through different update paths. Even if they do, that would be a coincedence. Pls note that this is my conclusion and I do not know the internals of the product versioning system. Pls check the following article for the frequency of the updates: Description of the standard terminology that is used to describe Microsoft software updates http://support.microsoft.com/kb/824684. Also see Brian Smith’s note in the blog article mentioned above: “In most of the KB articles the term hotfix is used in place of Cumulative Update. They tend to be interchangeable terms – a Cumulative Update is just a hotfix built to a schedule.”