Dear all, I got a problem before an upgrade of my otrs system from 1.3 to 2.1.7. Here's after the phenomen by steps: 1) A client sends a mail to otrs system in order to create ticket : there no problem for that. 2) Into thi ticket, the agent respond to sender writing response : OK 3) The client received the response from the otrs system : OK 4) The client responds from this mail (including the ticket number in the mail subject) : BUT nevertheless the response does not increase the original ticket, I don't where went the respond. It is lost. I think that I forgot to do some things after my upgrade. Any Ideas ? Thanks in advance for your help Best regards Denis JULIEN