If you get an error message like the below picture when trying to sync, then the reason is what is highlighted in red (Server.AuthenticationToken.InvalidUserCredentials / invalid authentication token). Basically, it means that your login details are incorrect.
- Please login directly to your EndNoteOnlone account at www.myendnoteweb.com
- If successful login, please copy your login details into EndNote under Edit>Preferences>Sync
Notice! Copy and paste the details to avoid mispelling