Hi margalit, where do you access your calendar and contact list? For example, are they stored with Google, Microsoft/Outlook, or another website? Or did you have an add-on that made them accessible in Firefox? What happens when you try to access them, for example, Firefox can't connect, Firefox shows a blank page, the website displays an error message, etc.? ''If the problem is in the separate Thunderbird email program, let us know and a moderator can move your question to the Thunderbird section.''