On 21.2.2019 13.47, Lionel Elie Mamane via dovecot wrote: > I noticed a mail stuck in my mail queue. dovecot-lda was returning > error 64 Invalid parameter given. (EX_USAGE). > > Weird, weird, weird. After some sleuthing, I found the sender address > was firstl...@domain.tld, with a UTF8-encoded Unicode U+FEFF ZERO > WIDTH NO-BREAK SPACE character (AKA byte order mark) between "First" > and "Last" :) > > Since that is passed as the -f parameter to dovecot-lda, it was giving > the 64 error.
Your MTA should not be passing this along. Aki
