Zen 6.5.2 on Netware 6.5.5, Zen Agent 6.5.2 on WinXP, Novell Client

Application is associated with a group of users, icon set to display on
the desktop and the App Launcher window. One member of the group has
lost the icon from the desktop - it was there previously but no longer
shows - though it is still in the App Launcher.

NALDiag shows the PPM app is associated, in the Filter column it shows
Passed (Visible).

Another app which has dissappeared from the desktop is simply a
shortcut to Groupwise web access which is associated at a container a
two levels above the user's container. This still appears in the NAL
Window just not on the desktop.

What can I check to find why these icons no longer display on the