which encryption program did you use. If it was something like AxCrypt and you can remember the password, reinstall the program. I am assuming your encrypted document was on a backup disc and not formatted.
How did formatting the computer make you forget the password?
The encryption can be broken with software but your best method is to try all the passwords that you might have used. Although not recommended, most people use a small selection of passwords for everything. I think I only use about 20 passwords myself.
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