ndOffice for Adobe Install
To Install the ndOffice for Adobe find the Direct Download Links page on NetDocuments' website, going to this URL: https://support.netdocuments.com/s/article/205219960
Find the ndOffice download links and the file types off to the right.

If you are installing the Adobe plug-in for the first time, the process will be fairly straight forward. You may run either the ndOffice .exe or the ndOffice .msi in conjunction with the ndOfficeAdobeSetupX<64 OR 86>.msi.
-EXE: Running the .exe file contains both the ndOffice application and the ndOffice Adobe plugin. To install both, run the .exe file. The installer will identify whether your machine has 32-bit or 64-bit Adobe and install the correct version of the Adobe plug-in.
-MSI: If you wish to install ndOffice and the Adobe plug-in using the .msi files instead, the ndOfficeSetup.msi file and the ndOfficeAdobeSetupX<64 OR 86>.msi files will need to be run. This can be found within the .zip files, which correlate with whichever version of adobe you have. For example, Adobe Pro is a 64-bit or X64 application, so you would install the x64 ndOfficeAdobeSetup.

If you already have the ndOffice plug-in, and you do not have the ndOffice for Adobe plug-in, you likely need to download the .zip file from the Direct Download Links, so that you can get the correct .msi for your Adobe Application.