Quicken 

Quicken, like many other "secure" systems, doesn't actually encrypt data at all, but rather stores the password and checks if the uses
knows it before allowing access to the file. I've found this method extremely common, especially on database systems. Oh, well. 

All we need to do is convince Quicken that we haven't got a password at all. You'll need a good hex editor to do this. Open up the
.QDT (or better yet, a backup of it) and set the bytes at the following offsets to 00h: 17445, 17446, and 17447. That's it! Or at least,
that was it until Intuit developed Quicken 5.0.... 

For Quicken 5.0, you need to open the .QDB and zero out offsets 4425, 4426, and 4427. Same idea, different file, and different
location. Not bright, are they? 

Quicken 6.0 apparently uses 4425, 4426, and 4427 again. Thanks to Rudy Montoya for letting me know about 6.0...