Documents and Settings: If several people use the same computer, and each user logs on with his or her own password or username, you might have created the file while another teacher or student was logged in. Depending on your system configuration, you might be able to open and search other users' folders, or you might ask each user to login and help you look.

Program Files: Program files -- the files that Microsoft Word, Internet Explorer and other computer programs need to run -- are another, although less likely, place to look for a missing file. On rare occasions, a file might get saved in the folder of the program used to create it.

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