Hi Elizabeth,
Check in Tools=>Protection on the document to see
if that's in play. You can also try opening a new,
blank document and use Insert=>File to pull in the
other document to see if that helps.
If Word shutdown on its own at some point or the
file folder permissions don't allow file deletions
it's possible that there are some left over temp/lock
files still around.
With Word not running do a search for files using this string
~$*.*;*.tmp
delete them and see if you can then start Word and use
the file.
=========
When opening a Word document receive a file in use error:
document.doc is locked for editing by 'user'. Neither
the user or an administrator can change, unlock or
deleted the document. >>
--
Let us know if this helped you,
Bob Buckland ?
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MS Office System Products MVP
*Courtesy is not expensive and can pay big dividends*
Office 2003 Editions explained
http://www.microsoft.com/uk/office/editions.mspx