Getting into a password protected XLSX File, am I stuffed?

[XeNoN89]

CEO urgently needs to get into an xlsx file that nobody in the office knows the password to. Any free software around I have found so far hasn't worked. Opening the file in notepad I can see it is encrypted using 128bit AES

Is this hopeless?

 

[bledd]

http://www.elcomsoft.co.uk/aopr.html

Try something like that, they typically have a trial that will reveal the first 3 letters.

 

[DaleTheWhale]

Where did this file come from, who created it! DUN DUN DUNNN.