My dropbox icon from the top bar has disappeared. I have tried to uninstall and reinstall as suggested in an answer to someone with a similar problem but sudo apt-get remove dropbox gets the reply "virtual packages such as dropbox can't be removed". Then I tried sudo apt-get remove dropbox; rm -rvf ~/.dropbox ~/.dropbox-dist (from the dropbox site)which removed some items but not dropbox itself. What do I do? I am using 12.04 and am new to ubuntu. I still have the launcher icon and the folder but changes/new files don't upload automatically.