FWIIW I had this message still in drafts /usr/bin/imaptest - append=100,0 logout=0 host=xxx port=143 user=xxx pass=xxx seed=100 secs=1 clients=1 mbox=64kb.mbox box=inbox/test msgs=100000 And inbox/test does not exist, results in: Fatal: master: service(imap): child 20282 killed with signal 11 (core dumped)