File - New Calendar
 Select 'On the Network', NEXT

I have been using the Lightning calendar synchronized with my Google calendar using Provider for Google Canendar for several year without issue. Today all entries have disappeared from the Lightning calendar. When I view the Google calendar in a browser all calendar entries are present. When I clicked 'Synchronize' on Lightning I received a very brief message 'Checking calendar', for what must be a couple of hundredths of a second, but no synchronization ocurred. I have installed the latest versions of Thunderbird, Lightning and Provider for Google Calendars. I deleted the Lightning calendar and attempted to create a new one, however I cannot follow the procedure given here: https://support.mozilla.org/en-US/kb/using-lightning-google-calendar I did the following steps: File - New Calendar Select 'On the Network', NEXT At this point the procedure tells me to: 'Choose Google Calendar from the available types of calendars and paste or enter the URL to your calendar.' However as soon as I select 'Google Calendar' the box for entering the URL disappears. When I press NEXT I am invited to enter an e-mail address, at which point I entered my Gmail address, then pressed NEXT. I then got a 'Create New Calendar' window, with the message 'please select the calendars and task lists you would like to subscribe to'. However the box below is blank. Any suggestions greatly appreciated. Thunderbird version 31.2.0 Lightning version 3.3.1 Provider for Google Calendar version 1.0.1 Windows 8.1