Good afternoon MattyB
How much in fiscal terms is your spreadsheet worth to you, because you may well have to pay for it.
Firstly, if your passwords are relatively simple (either an English word, or less than nine characters long) then try this:
http://www.download.com/Free-Word-Ex...-10249516.html
It's free and should be fairly successful, if you haven't made the password too complex.
If that fails, then you'll have to pay someone to crack it for you, or buy some software to do so. These sites below each list a number of 3rd parties to do this.
http://www.cpearson.com/excel/password.htm
http://j-walk.com/ss/excel/links/pword.htm
HTH
DominicB
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