You have a few options here first is if it is the little astreks ( ****) you can use SnadBoy's Revelation, which is here http://www.snadboy.com/ .
If it is in a file and encrypted then more than likely you can get a brute force password cracking program like John the Ripper, Brutus, Rainbow Crack, and a few others. (I will provide you with links to all that I can find) Now you need a password listwhich you also download or you can make just make a txt file with passwords that it could be listed one underneath the other. So now say that that the password looks like this "dqX*[IlMIL>J" then make a file saved in txt format aswell and it will look like this:
user:dqX*[IlMIL>J
Now you open the password cracking program then point it to crack the file with the user:dqX*[IlMIL>J and make it use one of the password lists you made or downloaded.