Permission Error When Saving Word 2000 Document. (V4.0.138377.779 X32)

Windows XP Home SP3: MS Office 2000 SP3. Configuration Report Attached.
Symptoms. Open previously saved doc and SAVE without any changes, no problem
Open previously saved doc, make changes and SAVE - Permission Error and NO save.
Open previously saved doc, make changes and SAVE AS with new tiltle, no problem.
To resolve the problem ( help from CIS AV Forum), added c:*.doc to Exclusions in AV.
Running in Admin account but the problem applies to other users of the PC as well.
Note. Understand problem was apparent in versions 3.8, 3.9 and 3.13 of CIS. However, another member of the family running 3.14 on another PC with the same Office version cannot replicate the problem - it works OK.
Help Please.

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