I had this problem myself a while ago. To fix it, display your list of subscribed threads. Check the "Notification" check box (which should check every item), scroll to the bottom of the page and in the "Selected Threads" drop down list, select "No Email Notification". If you have more than one page of subscriptions you'll have to repeat for each page.
Bruce Dickson 2013 Thor Challenger 37GT, 5 Star Tune, Safe-T-Plus Steering Control with Air Trim, Roadmaster front and rear Sway Bars, SuperSteer rear Track Bar, Crossfires, 2012 Honda CRV on Blue Ox Aventa LX tow bar. Full timers since Jan 2012.