[Added 28 Sep 2017] If you are not using Gmail for Dropbox but actually have one, I guess (not personally tried though) you can change your email to G
We have updated the Dropbox icon in your system tray. When everything’s synced, you’ll now see a Dropbox icon without a checkmark. [Learn More]
Thanks for posting on Dropbox Forum! We´d love to help with this issue.
In general the message "Access Denied" means the Dropbox desktop