A disconnection can occur for numerous reasons which is not only a disruption from our server, but the connection to it which leaves too many variables that are outside our control.
However we do offer assistance in two ways. First if you were in the middle of sending an email we auto-save the email every minute. See screenshot below for location.
Next in the popup window that shows a disconnect, if you are using Firefox browser there is a Try Again link which you can safely use. To see this button you may need to make the small popup window slightly larger as shown below.