Look at
*my* tray
...
Possibly related:
I did a bunch of Windows (7) security updates yesterday.
Rebooted fine.
I restarted explorer.exe later (via Process Explorer), tbh, I cant remember why
Later, Windows would not close down - I had to force a reboot.
Today, the tray was fine initially and I havent been doing any funny business...
PS the popup with hidden icons shows as expected