Adobe PDF Link Helper is missing

I do not see either PDF Link Helper or Adobe Acrobat SharePoint Open Documents Component in 64 bit IE9. I see them both in the 32 bit version. Are they both for displaying in a browser? The root issue I am trying to solve is getting the SharePoint 2010 Acrobat X integration to work, The original symptom was that a user would check out a pdf file from a SharePoint library, edit it (using the comment feature in Reader) and then Save or Check In. Either action would result in a Cannot Access the Network error. Looking at the HTML traffic in Fiddler showed the error text had nothing to do with the problem, which seemed to be about attribute values. Anyway, I put this on the back burner for a couple months and returned to it recently. It now works on my machine in a 32 bit browser. (ACCEPTABLE RESTRICTION). My coworker still gets the original error. I poked around and found the SharePoint Open Documents add-on on my machine and not hers and suspect it has something to do with the difference in behavior. So I am trying to find out what it is supposed to do and if it really is relevant, how to cause it to be downloaded on other people’s machines. I have been through the server configuration steps listed in Chapter 13 of the Acrobat Admin Guide.