Hi all Thanks for your valuable Inputs!
@Peter: we did enable the logs with flag_change. We will try to catch the logs when the issue appears. We try hard to reproduce, but it happens rarely. @Alex: in the logs we do not see any message "Missing middle file seq=..". But we will check this more in detail. Does the "mbox_lazy_writes" settings only affects the mbox backed? In our case we use mdbox, thus disabling this setting would not have any effect, right? regards plataleas On 12/06/2016 11:34 AM, Peter Chiochetti wrote: > Hi, There is a plugin "mail_log" that you can use to audit what > users/user agents are doing, probably mail_log_events flag_change is > helpful? >