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