SMTP response to 450 error

When an outside SMTP server tries sending my SMTP server mail, and my
server issues the 450 error response, what is the proper action for
that outside SMTP server to do?

I know my server has been rejecting a fair amount of mail due to being
on a black-list, and doing domain (mx record) checking. My server
issues the 450 error to other smtp servers when there is no domain, or
no mx record detected for the domain, yet the outsite smtp server keeps
attempting to deliver that mail for days.

Should a SMTP server stop trying to attempt mail delivery once it
receives the 450 error from another server, or should it reattempt
delivery?

Re: SMTP response to 450 error

mikedawg@gmail.com writes:

> When an outside SMTP server tries sending my SMTP server mail, and my
> server issues the 450 error response, what is the proper action for
> that outside SMTP server to do?
>
> I know my server has been rejecting a fair amount of mail due to being
> on a black-list, and doing domain (mx record) checking. My server
> issues the 450 error to other smtp servers when there is no domain, or
> no mx record detected for the domain, yet the outsite smtp server keeps
> attempting to deliver that mail for days.
>
> Should a SMTP server stop trying to attempt mail delivery once it
> receives the 450 error from another server, or should it reattempt
> delivery?

4?? codes mean: temporary problem, try again later"
5?? codes mean: permanet problem, abort furher delivery attempts

--
[pl2en Andrew] Andrzej Adam Filip : anfi@priv.onet.pl : anfi@xl.wp.pl
http://anfi.homeunix.net/

Re: SMTP response to 450 error

Thanks for the info, I didn't know that.

Thanks

Mike