This is the beginner's challenge in a series about M-138, a manual cipher of the US army which has been relatively save at the beginning of world war 2nd. Part 1 of the series is a ciphertext-only challenge whose key is largely known.
Read more...

What is the reason for unpublishing the three M138-Challenges? If they are too difficult, they could be published as level x challenges.

What is the reason for unpublishing the three M138-Challenges?

The reason was that at least for part 3 there are very many meaningful solutions and the solver cannot decide which is the right one – this caused frustration for some solvers. So we are planning to add a crib and/or a hash value to the descriptions, which enables the solver to check by himself whether he found the right solution or which shrinks the solution space.
After that we publish these challenges again.
Any ideas on how to improve these challenges are welcome. You also can send me a PM.
Best regards, be

Hello

I'm very sure that I have the correct plaintext.
But the solution (in capitol letters and without spaces) is not accepted. I tried it several time…

What could be wrong???

Best Regards,
T. Wagner

Dear Wagner

The solution is accepted as capital letters and without spaces

Please send me your solution in PM in order to check it

Best Regards
George Theofanidis