Moved to correct forum. Has nothing to do with Macworld. Please read our forum descriptions before posting.
If you've forgotten the password to your Excel document, you can use one of several programs to recover it. LINK Note that the link is for the Windows versions. However, with some smart searching you should be able to find something that will work for your Mac.
You can always move the file to a Windows machine and try to recover from there with one of the above methods.
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