I have a few rar files that I have lost the password to, these are very important files and I have to get into them. I have heard of several programs to crack rars but I was told that these programs will take a long time to crack a good password and may not even work. Is this because they use a "brute force" technique? The passwords on these files are around 15 characters long and are probably mainly composed of non-alphanumeric characters. Like I said, these files are very important, if they weren't I wouldn't bother. Any response will be GREATLY appreciated.