General Info

This trick is based on Multiple Instances On Linux Or Mac OS X. It keeps Dropbox syncing your files after your Mac is booted, even if you aren’t logged into your Mac or Mac Server. It has been tested on a Mac Mini server running OS 10.6.5 and Dropbox 1.0.10.


  1. Log into your Mac as the root user. If you don’t know how to do this, see:
  2. Next, open the Finder and select Go > Go to Folder…. Type /etc in the dialogue and select Go.
  3. Now find the file rc.common. Right-click and duplicate rc.common, renaming the duplicate to rc.common.backup.
  4. Then open rc.common using a programming text editor like TextWrangler ( At the very end of the file, add the following line;
    su username -c "/Applications/ &"
  5. Replace username with the shortname of the Mac OS X user account you are trying to keep Dropbox running on while logged out. If you don’t know the shortname, you can also find it on your Macintosh HD under the Users folder.
  6. After you have saved rc.common, restart your Mac. Upon boot your Mac will now automatically start Dropbox for the user account you specified in rc.common. You can log in and out of the user account as you wish, and it will not stop Dropbox from running in the background.

Known Bugs

  • The only bug I have found with this is that the Dropbox menubar UI no longer shows up when you log into the automatically started user account.
  • Sometimes it’s not syncing when changes are made to the original destination (when using symlinks).
  • This also won’t work if you have FileVault enabled.