Why the applet won't connect? After connection attempts it remains disconnected

After system update, the applet does not connect to the cloud anymore.

The symptom is that the applet is shown with an exclamation mark on it, and when "Connect" is clicked (left-click on the applet, then Connect), it says "Connecting" for a small period of time, and then disconnects.

To workaround this issue, first check your config file for the sync daemon at ~/.config/ubuntuone/syncdaemon.conf

If you have bandwidth_throttling enabled (you'll see on = True below the [bandwidth_throttling] section), please disabled by setting it to False.

To do this, quit the client (right-click on the applet, then Quit), and edit the config file pointed above so throttling gets disabled. For example you can use a config like this one:

nessita@dali:~$ cat ~/.config/ubuntuone/syncdaemon.conf
[bandwidth_throttling]
on = False
read_limit = 0
write_limit = 0

Then, restart the client, It should now stay connected.