I would like to unzip an xlsx file, modify one of the xml files, and then zip
it back up. I want to do this from the desktop, not programmatically.

To test this, I have done the following:

1. Change excel file extension from xlsx to zip
2. Extracted the file in the zip archive to a new folder.
3. Zipped up this new folder and its contents.
4. Changed the extension of the zip file from zip to xlsx.

However, when I try to open the file from step (4) above, I get an error
from excel saying that the worksheet is not formatted correctly.

Is there a way I can overcome this error?

Thanks ... bill burrows