What would cause the Application Explorer window to be blank?

I have a user with this problem on their workstation. The
workstations appears to be registered correctly, they're logged into
the network correctly, but nothing appears in the Application
Explorer or the Application Launcher.

if I click on the Application Explorer icon in the system tray and
select Properties -> More, the login information window is blank.

However, if I use F2 to view the advanced information it shows the
user logged in and the workstation helper connected.

I've tried uninstalling & reinstalling the zenworks agent, but that
didn't help. We're running version