This solution is for Windows 10 x64.
Steps the follow :
1. uninstall MS word from your pc.
2. Install MS word 2010.
3. Install also MS word 2016, the two version 2010/2016 can be simultaneously installed. But, the word 2010 should be installed first.
4. install MS word plugin from Mendeley.
5. Finally, Mendeley will normally work on MS word 2016 (also for word 2010).