I run Ubuntu 14 LTS, and ran get update and get upgrade just now,
I have a user that runs Dropbox, and it is running great,
I created a new user and try to link it to Dropbox too and getting some weird massage that i can't sign in to Dropbox because my version is not updated, but it works great on the old user, i tried to disconnect and reconnect and it works well.
I can't seem to find any update for Dropbox in the software center...
Is this is a known bug?
Try getting a fresh release from:
https://www.dropbox.com/install?os=lnx
Make sure that your browser is logged out from dropbox.com when you visit this link; otherwise download links are not shown.
Instead of getting a fresh version from the Dropbox site, i removed it and reinstalled using the Ubuntu software center, and now it works.