The email you was a automated emails sent to inform you of replies to threads you have started or replied in as you can set what to get emails notifications for on https://support.mozilla.org/en-US/users/settings There should be a link to the thread in the email sent. While on this site, look at top right and hover over your judy58 name and either click on My Questions or on View Profile to then see search links for both threads and replies you posted here. You have only posted here two times so far and your other thread is at https://support.mozilla.org/en-US/questions/1499983 So you know how to reply in a thread, scroll down to the '''Post a Reply''' box, type in your reply then click on the blue Post Reply.