If you're getting unwanted emails when someone posts on the forum, you can do the following.

Click on "Settings" at the top of the forum page. On the left side of the page, click on "General Settings". Go to the section for "Messages and Notifications".

Under the Default Thread Subscription Mode, use the drop-down arrow and choose "Do Not Subscribe", click on "Save Changes".

Then, under where you chose "Do Not Subscribe", click on the little blue link that says "Subscribed Threads", click on "Empty Current Folder".