Word 2000 under WinXP won't open password protected .docx files

When I try and open a password protected .docx file with Word 2000 a
small window appears with this message in it:
__________________________________________________ ____
The document name or path is not valid.
Try these suggestions.
*Check the file permissions for this document or drive.
*Use the file open dialog box to locate the document.
__________________________________________________ ____

Those "suggestions" don't give me much of a clue.

The same file will open OK in later versions of Word or Open Office,
after asking for and receiving the password.

Password protected .doc files created with Word 2000 will open correctly
in Word 2000.

Is there something I can do to open those password protected .docx files
in Word 2000?

Thanks guys,

Jeff
--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.