Q: Why doesn't John load my password file? It says "No password hashes loaded".
A: Your password file might be shadowed. You need to get both /etc/passwd and the shadow file, and combine them into one file for use with John. Please refer to EXAMPLES. As the system administrator, you're supposed to know the name and location of your shadow file.
A: All of the password hashes found in the file (that John recognizes as such) might be already cracked by previous invocations of John.
A: The file you're trying to run John on might in fact not be a password file at all.
A: Your command line syntax might be wrong, resulting in John trying to load a wrong file.
A: Your password file format or hash type(s) might not be supported by John, or at least by the version and build of John that you're using. If you're positive that this is the case, you may want to check the contributed resources list on John the Ripper homepage for a suitable patch and, if unsuccessful with that, post a note to the mailing list (see CONTACT) including a sample password file line that John does not load (please make sure that the password is already changed by the time you post).