How to recover RAR passwords?
RAR/WinRAR archiver version 2.x used its proprietary, but rather strong encryption algorithm. At least no RAR 2.0 attacks were known except brute force. Starting from version 3.0, RAR has been using a strong AES algorithm, which doesn’t allow any attacks more effective than the brute force. Besides, the encryption is implemented so that brute force speed on modern computer is very low, about 100 passwords per second. This carries inference that RAR 3.x system is the strongest between popular encryption systems in the context of brute force. This means you couldn’t recover RAR password longer than 6-7 symbols if you have no information about the password.