Click on
My Controls.
Then in the "Subscriptions" section, click on "Forums".
Check the boxes next to the forums, make sure the dropdown is "Unsubscribe" and then click the "with selected" button.
You should now be unsubscribed from the notifications. If it doesn't work, send me an email or PM and I'll manually unsubscribe you via the admin control panel.
While we're on the subject of emails: please make sure that the email address that you registered with is still valid. If it is not valid, the britboard server will receive an error report for every topic subscription notification, every PM notification, and every email that another member sends to you.
If you use an email address that regularly causes error reports I reserve the right to set your forum registration address to a random address at mailinator.com until you supply an address that works.