Emails getting rejected

[matt_thomson]

Hi I sent out about 50 emails from a mailing list and got 5 bounceback
messages, they went like this:

1:Deferred: 451 Temporary failure, please try again later.
Message could not be delivered for 5 days Message will be deleted
from queue

2:Deferred: 450 Recipient address rejected: Greylisted for 5 minutes
<<< 554 Error: no valid recipients Message could not be delivered for
5 days Message will be deleted from queue.

3: Deferred: Bad file descriptor Message could not be delivered for 5
days Message will be deleted from queue

4:Deferred: 421 Message rejected Message could not be delivered for 5
days Message will be deleted from queue

5:Deferred: 451 4.7.1 Please try again later Message could not be
delivered for 5 days Message will be deleted from queue

These 5 messages came back 5 days after the mail was sent. I guess
spam/virus filtering or greylisting is responsible, though I'm not
sure.

Is it common to have emails rejected like this, and does anyone know
what I can do to reduce/fix these.

Thanks.

Matt.

[David Hawke]

matt_thomson wrote:
> Hi I sent out about 50 emails from a mailing list and got 5 bounceback
> messages, they went like this:
>
> 1:Deferred: 451 Temporary failure, please try again later.
> Message could not be delivered for 5 days Message will be deleted
> from queue
>
> 2:Deferred: 450 Recipient address rejected: Greylisted for 5 minutes
> <<< 554 Error: no valid recipients Message could not be delivered for
> 5 days Message will be deleted from queue.
>
>

These first 2 sound like grey listing tools - spam engines seem to hit
the connection hard and move on. I've seen some retry up to 10 times,
rapidly, then they give up and move on

> 3: Deferred: Bad file descriptor Message could not be delivered for 5
> days Message will be deleted from queue
>
>

Couldn't connect to the mail server - this looks like an issue with the
server (bad file descriptor)

> 4:Deferred: 421 Message rejected Message could not be delivered for 5
> days Message will be deleted from queue
>
> 5:Deferred: 451 4.7.1 Please try again later Message could not be
> delivered for 5 days Message will be deleted from queue
>
>

These are also connection issues - either can't connect to to the server
or it won't accept mail for the recipient

The 5 days in queue is the local server trying to deliver and being
blocked - eventually it gives up

David H

[Chris Burgess]

If this is greylisting, it's an odd configuration (the error message says otherwise)

[David Hawke]

Chris Burgess wrote:

If this is greylisting, it's an odd configuration (the error message says otherwise)

On 12/02/2008, at 12:50 PM, David Hawke wrote:

1:Deferred: 451 Temporary failure, please try again later.

This wording is consistent with a couple of the greylisting tools

  Message could not be delivered for 5 days Message will be deleted

from queue

This looks as though the retry attempts were sufficiently close together for the greylist tool to blacklist

David H

[matt_thomson]

If it is potentially grey listing should I just send the 5 again and
see what happens. Is there anyway to reduce emails getting greylisted/
bounced?

[David Hawke]

matt_thomson wrote:
> If it is potentially grey listing should I just send the 5 again and
> see what happens. Is there anyway to reduce emails getting greylisted/
> bounced?
>

How are you sending them? Are you feeding them to an MTA (Mail Transport
Agent) or are you using the mail() function?

I'd suggest that you do a search for greylisting and proceed from there
- normally if you connect (retry) too frequently) the greylisting
changes to blacklist for some defined period. This is highly dependant
on the methodology employed.

I'd also suggest that you verify the email addresses which bounced
before you go any further.

David H