The "do you need help thread" is throwing up an error from the General subforum

I can see the stickied thread in the General subforum, but when I click it, this appears (entering the thread works fine from the Health and Advice subforum):

Server Error

Undefined index: isThreadBanned
  1. XenForo_Application::handlePhpError() in ThreadBan/ControllerPublic/Thread.php at line 300
  2. ThreadBan_ControllerPublic_Thread->_getBanNotice() in ThreadBan/ControllerPublic/Thread.php at line 24
  3. ThreadBan_ControllerPublic_Thread->actionIndex() in ChangeThreadStarter/ControllerPublic/Thread.php at line 7
  4. ChangeThreadStarter_ControllerPublic_Thread->actionIndex() in XenForo/FrontController.php at line 347
  5. XenForo_FrontController->dispatch() in XenForo/FrontController.php at line 134
  6. XenForo_FrontController->run() in /home/davidn/public_html/xenforo/index.php at line 13