Did you check for a bad LDB file like Bob suggested? On the one user that having the issue, have them completely close out of the DB. Look in their local directory that stores the DB. If there's still a LDB file in there ([your_DB_filename].LDB) after that user has completely exited the DB, delete the LDB file. This file should be removed and recreated each time the user closes and opens the DB, but for various reasons, it doesn't always happen properly.