Hello Stefan
On 14.08.2012 16:11, Stefan Rothenbuehler wrote:
On 08/14/2012 03:42 PM, Tobias Oetiker wrote:
occasionally we get mail bounces from bluewin that look like this:
Jul 6 13:17:31 xxxx postfix/smtp[30166]: xxxx: to=x@bluewin.ch, relay=mxbw.bluewin.ch[195.186.99.50]:25, delay=2, delays=0.02/0/0.05/2, dsn=5.0.0, status=bounced (host mxbw.bluewin.ch[195.186.99.50] said: 551 551x@bluewin.ch Account administratively disabled. Please try later (in reply to RCPT TO command))
Those mails are rejected as the recipients account has been administratively blocked. This can have various reasons which I'm not gonna list here.
I do see a discrepancy here. The mail account is temporary "closed", as you say and also the text "Please try later" does indicate. But the error 551 is a permanent error and the sending server will purge this e-mail from the queue and notify the original sender of the non-delivery.
It would probably be a good idea to respond only with a 4xx error, which is temporary. So the sending server could queue the e-mail and try again later, without any interaction from the end user. Usually the sending mail server does notify the original sender, after delivery of the e-mail has failed for several hours. It then will try up to 5 days to deliver this e-mail, before the e-mail will be purged from the queue and the original sender being notified.
But sure, this depends on how long such accounts are administratively blocked. If it is only for a few days, then a 4xx error would be much friendlier, also to the affected Bluewin customer. If one of this customer is also subscribed to several mailing lists, then there is a very high chance, that he will be automatically unsubscribed from them as well.
Just my 2 cents.
bye Fabian