I am far from an expert on email, but I can offer a few thoughts.
Has email ever worked, or is this a more recent problem? If it is more recent, you would need to explore what has changed. The change could be from a change in Moodle or a change on your server.
You might also try going to Admin | Server | Email | Outgoing Mail configuration, and then try "Test outgoing mail configuration." If this works, then it might point to something wrong with your Forum configuration.
Well, this is the best that I can do. Others here will improve upon my ideas.
Has email ever worked, or is this a more recent problem? If it is more recent, you would need to explore what has changed. The change could be from a change in Moodle or a change on your server.
You might also try going to Admin | Server | Email | Outgoing Mail configuration, and then try "Test outgoing mail configuration." If this works, then it might point to something wrong with your Forum configuration.
Well, this is the best that I can do. Others here will improve upon my ideas.