Disappearing Act

In A2003, we have a multi-tabbed form. One of the tabbed forms is a data
entry form with a subform containing a memo field, some dropdowns and some
'action buttons' (i.e Add New; Edit, etc.). On one of the user's subforms,
the buttons and dropdowns have disappeared, leaving only the memo field
visible. If he 'right-clicks' anywhere on the sf, the context menu appears,
presenting a selection of 'Subform'. The options are 'Form', 'Datasheet',
'Pivot Table' and 'Pivot Chart'. In selecting 'Form', all of the dropdowns
and buttons 'magically' appear on the subform. I'm sure if his front-end is
re-installed, his form would behave and look like everyone's else form. But
the larger issue is, "What is wrong with this user's form to make those
controls disappear until he goes thru the above described extra steps?

Bewildered...
Earl Anderson