I know that if a user has several calendars listed under "other calendars"
and they are viewing multiple calendars at once (check boxes are checked in
the calendar list) and they close and re-open Outlook, the checkboxes are
cleared and they have to reselect them again.

But can you think of any reason why the checkboxes might get cleared
(de-selected) while Outlook remains open? i.e. - the user switches from
calendars to email and when they come back to calendars the other calendars
are no longer checked (except for the main calendar)

Could this possibly be caused if the Outlook client stays open but loses
connectivity to the exchange server? If so, could this be fixed if the user
was set to use cached mode?

Thanks...
Mike