If problems started after an update, try running upgrade.php at yoursiteinstallationlocation/upgrade.php. It's possible this file didn't get automatically processed to completion and your manual run of it will fix it.

Sometimes, for some sorts of problems, people have found that clearing their cookies or trying a different web browser fixes their problem.

Otherwise, please contact WSN support. We provide free site inspection and repair service to go into your site and fix it for you.