I am using Windows 10. The specific update is X9.3.3. It’s a pretty major update apparently, because once you update, your database is converted and you can no longer use it with an earlier version of EndNote.
(I do not understand what is so major with this update because I did not notice any significant improvement over X9.3.2—the only changes were those that I mentioned plus another problem I forgot about: EndNote now sorts special characters after the alphabet, creating problems for those who use special characters for transliteration from other alphabets. Bottom line, this new update is a disaster. I’ve never posted or commented on a discussion board in my life about any other program, but I feel completely hamstrung by this new EndNote.)