You can backup your reference library by saving a copy of EndNote files in a local drive of your PC, USB device, or cloud space. We recommend you to backup your library in more than one location for prudent.
Save as a compressed library is particularly helpful if you wish to send your reference library to another person. This is because this process will generate only one file which can be easily sent via cloud drive or attached in your email.
EndNote provides a cloud space (EndNote Web) for you to backup your reference library. However, we DO NOT suggest synchronizing more than one reference libraries from your EndNote desktop onto your EndNote Web. This is because when you synchronize more than one libraries from the desktop version onto the EndNote Web, all references from your second EndNote desktop library will be merged into your existing EndNote Web library.
You can consider backing up your reference library using a third party cloud space (e.g. Google Drive, Dropbox, etc.) by saving your library onto these cloud-based drives (Save a Copy), so that you can backup multiple reference libraries.
If you have decided to synchronize the library with EndNote Web, you can follow the steps below: