[slodave]

You should find the file here:
C:\Documents and Settings\Administrator\Application Data\Mozilla\Firefox\Profiles\g9wdcwwl.default

Replace "Administrator" with your log on name. Or, search for "bookmarks.*" (without the quotes). If you are lucky, you'll find a "bookmarks.bak". IT may be a recent backup. Save a copy and rename to bookmarks.html. Make sure it is in the correct path. This should get your bookmarks back.

It is odd that a FF update would do this though.

Dave

There also seems to be a directory under the above path named "bookmarkbackups". Check here as well.