When you sign into Yahoo! Groups, you use a Yahoo! ID. This ID is used to recognise you whenever you access online features of Yahoo! Groups.

However, when you join a group, it is your email address that’s subscribed, not your Yahoo! ID. In order for us to know which groups you’re a member of, you must ]link your email addresses to your Yahoo! ID. Once that’s done, you’ll see all the groups your email address is subscribed to listed on the My Groups page.