When sending a an error in soap authentication occurs - no error is sent, and after a few attempts the process is stuck. I have no indication on what problem occurred since nothing is returned from Marketo. After a few attempts i found the problem, the Soap API->Encryption Key changes, so i changed it. But that was too late, now all attempts were stuck. After restarting my system - the client of Marketo - it started to work.
The error indication did work before, so this is a regression. As for the stuck - i don't understand why this happens. Is there some kind of attempts limit?