Just sharing that the company I have done work for encountered the same issue. Since we didn't want to spend the time changing it and they elected not to have me write the code to automate it, we took the cowards way out.
We placed the files on our file server and only those with accounts can access the files. Said accounts have passwords and we have a "cheat-sheet" with known passwords and as our group works on the documents, we change them as needed.
The code is trivial in Visual Basic and the Office package, but I can't offer such a service.
Bob
I need to change the passwords in hundreds of MS Word and Excel files =GLOBALLY= without having to open each file manually and changing the darn password. I cant afford hundreds they want for the filemaker password change tool. please help

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