If only I can rate this a zero. Keeps forcing me to upgrade and sign in just to access a folder that has been shared by collaborator. Even when it's already shared on their side (they even showed a screenshot saying my account is inside the shared list), it kept saying I can't access the folder unless I upgrade (?!!). There's literally NOTHING inside my Dropbox folder and it kept spamming me with email saying I'm out of space. Maybe it's time to learn from your other competitors.