If your installation of EndNote fails while the Export Helper add-on is being installed, this is because of a known issue currently being investigated by the software developers. Export Helper is not required if you use Firefox as your browser because Firefox allows exports to be opened without an add-on.
When installing EndNote, choose the custom installation option and disable the Export Helper feature by unticking its checkbox. Installation should now proceed without issue.
If you are still having EndNote installation issues contact AskOtago:
Tel +64 3 479 7000 or 0800 80 80 98
If you still require Export Helper, it can be downloaded separately as a stand-alone installer.