Every year or so, NetDocuments will update its Active X Controller. This is usually not a big deal, unless you don’t have admin rights to install programs, or something just goes wrong. If that is the case, you need to download the active x controller and install it.
NetDocuments just did this in the beginning of February 2018, so it should be awhile before we have to do this again.
If you are in Europe or Australia, check out this page for your controller.