This is the third break of the M4 Project:

Ciphertext (stripped of indicator groups):

ykaenzapmschzbfocuvmrmdpycofhadzizmefxthflolpzlfggbotgoxgretdwtjiqhlmxvjwkzuastr

Plaintext (as seen in the server logs):

Date: 2008-05-28 18:16:31
Score: 1863727
UKW: B
W/0: 368
Stecker: ANBJEZHKLRMQOTPVSWUX
Rings: AGM
Message key: UYV

ilpgureitanaffordianstandortquaadcccvberneunneunzwefahrtzwonulshexscharxhorsthco

Plaintext (with adjusted rings and message key):

UKW: B
W/0: 368
Stecker: ANEZHKIJLRMQOTPVSWUX
Rings: AHM
Message key: UZV

steuerejtanafjordjanstandortquaaacccvierneunneunzwofahrtzwonulsmxxscharnhorsthco

Result:

Steuere Tanafjord an. Standort Qu. AC 4992, Fahrt 20 sm [Seemeilen].
        Scharnhorst

Translation:

A suspected plaintext had already been located in a BP Decode Teleprint [see Scharnhorst message]. Our break confirms that this is indeed the correct plaintext.

VX
ADM(1)                                                          128
TO I D 8 G
FROM N S                                   ZIP/ZTPG/200000
6475 KC/S       T O O 1925                 TOI 1830/26/12/43

FROM:  SCHARNHORST                                             7157 N
                                                               2830 E
   AM STEERING FOR TANAFJORD. POSITION IS SQUARE AC 4992,
   SPEED 20 KNOTS.
(DEPT. NOTE: THIS WAS THE LAST TRANSMISSION MADE BY
              SCHARNHORST)

0645/13/1/44+EE/AM

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