v4.72/bookmark problem...

[xinfo]

Been using Communicator v4.72 for quite some time... Anyway,
the browser crashed today and the user used ctrl+alt+del to
kill the process. When the browser was restarted, all of the
bookmarks were gone. I can not seem to find the bookmark.htm
for this user anywhere on the machine. Can anyone explain
why the bookmark file would have been deleted - there were
some rather important links in there.

TIA