sendmail -> lmtp 501 5.6.0 Data format error

Marc Roos M.Roos at
Fri Nov 29 00:48:03 EET 2019


Yes you were right, I asked also at sendmail and they also told me the 
smtp should stay. Seems to be working now with lmtp and sieve.

-----Original Message-----
To: Dovecot
Subject: RE: sendmail -> lmtp 501 5.6.0 Data format error

On Thu, 28 Nov 2019, Marc Roos wrote:

> When changing in a working setup
> From this
> MAILER(smtp)dnl
> MAILER(procmail)dnl
> To this
> FEATURE(`local_lmtp',`[IPC]',`FILE /var/run/dovecot/lmtp')dnl 
> MAILER(local)dnl
> I am getting these errors '501 5.6.0 Data format error' and '
> Unrecognized host name'.
> ...
> Eg. When I send email from gmail it looks like this
>    (reason: 553 5.1.2 <xxxx at>... Unrecognized host name

Just a stab (I toyed around with LMTP for a while and probably will 
eventually use it), but you probably need to retain


Sendmail has semi-cryptic documentation on what it does

Joseph Tam <jtam.home at>

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