Shared document on server opens as read only, no warning message

When I open a shared network file and someone already has
it opened (locked), it opens as read only, it gives no
warning or message that someone else has it locked or that
it is read only, the only way to tell it is read only is
that there is a note on the top of the screen saying it is
read only. We used to get a message that someone had the
file opened and would open as read only. It also used to
give the persons logon name. We have this problem
primarily with word files and shouldn't be a problem with
rights management (if no one has the file open it opens as
a writable copy). This happens with win 2000 and xp (dual
boot machine) but only on one users pc. Other dual boot
users have no problems like this. How do I get the
message back about the file being locked and who has it
locked?