Had to chance up on encountering this problem again. Fortunately, you need to follow these steps in order to add or remove passwords in MS Excel 2007.
I have made a youtube video to show both the short version and the long version on how to achieve this.
For the short version here are the steps
Open Microsoft Excel 2017 workbook
Open the file to add or remove the password
Click the ORB logo on the top left
Click the ‘Save As’ button
Click the ‘Tools’ button and then click ‘General Options‘ tab
In the ‘Password to open’ box, add or delete the existing password then click ‘OK’.
Click the ‘Save’ button. If prompted, click ‘Yes’ to replace the existing workbook
Enjoy
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