RE: sendmail -> lmtp 501 5.6.0 Data format error

On Thu, 28 Nov 2019, Marc Roos wrote:

When changing in a working setup sendmail.mc

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@gmail.com... Unrecognized host name gmail.com.)

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

MAILER(smtp)dnl

Sendmail has semi-cryptic documentation on what it does

https://www.sendmail.org/~ca/email/doc8.12/cf/m4/mailers.html

Joseph Tam jtam.home@gmail.com