Not never. One of the &quot;features&quot; of the Enigma was that a plaintext letter could never be encrypted to itself. An &#x27;A&#x27; going in could come out as any other letter, except &#x27;A&#x27;. German information security policies were generally pretty good. There were lapses, of course, and some of these were used to form cribs for a known plaintext attack on encrypted messages. But Enigma was&#x2F;is not invulnerable.<p>People found a couple encrypted Enigma messages after World War II. Here is a note from a group of people using modern computers and brute force to decrypt them:<p><a href="http:&#x2F;&#x2F;www.enigmaathome.net&#x2F;forum_thread.php?id=318" rel="nofollow">http:&#x2F;&#x2F;www.enigmaathome.net&#x2F;forum_thread.php?id=318</a>