[qmailtoaster] 511 sorry, no mailbox here by that name (#5.1.1 - chkuser)

[Micah Abrams]

List -

I have been getting sporadic reports from users that people attempting to
send them msgs are receiving a bounce with following error:

511 sorry, no mailbox here by
that name (#5.1.1 - chkuser)>

The users identified in the bounce msg definitely exist on the server (no
mis-spellings etc..) and these users are receiving mail otherwise.  I have
checked the smtp logs and they report Œfound existing recipient¹ when the
msg arrives.  This particular server is also very low volume.  Any
help/ideas would be much appreciated.  This is a new install using
qmail-toaster-1.03-1.3.15.

Thanks,

Micah