On Fri, January 23, 2015 08:56, Wietse Venema wrote: > > You have no control over how often remote senders retry deliveries, > nor do you control whether they will retry from the same IP address. > Some providers will retry from a random IP address in a large pool, > and those will never get past postscreen's deep protocol tests. >
We have had to whitelist some of our larger clients because of this very issue. We had one case where the same message was retried from at least five different IPs apparently because it was sent from a BlackBerry. We do not know how many it might have used eventually because we whitelissted the domain when we realised what was happening. -- *** E-Mail is NOT a SECURE channel *** James B. Byrne mailto:byrn...@harte-lyne.ca Harte & Lyne Limited http://www.harte-lyne.ca 9 Brockley Drive vox: +1 905 561 1241 Hamilton, Ontario fax: +1 905 561 0757 Canada L8E 3C3
