On 05/06/2023 07:49 PM, H wrote: > On 05/06/2023 03:24 PM, Atro Tossavainen via mailop wrote: >>> We are mailing from our own CRM system but using Ionos (1and1.com) as our >>> mail service. >> You're setting yourselves up to fail by mailing out of a server shared >> by thousands of other customers. The error messages you quote testify >> to that. Don't do it. >> > Understood. We plan to change the setup over the summer but until then we > have to work with what we have. When we change we will probably set up our > own postfix server for mail handling. I should have added that our future > "mass mailings" would be around 1000 emails per week or every two weeks, iow, > not too much. > > I did check the Ionos sending IP address on a couple of websites, including > mxtoolbox.com, and it is not listed. > I found this site https://learn.microsoft.com/en-us/exchange/troubleshoot/email-delivery/ndr/non-delivery-reports-in-exchange-online which I hope will help me interpreting the various responses.
Most immediate, of course, is to remove non-existing mailboxes. Sisimai - https://libsisimai.org/ - seems like a useful utility to parse bounced email messages. Is anyone on the list using it? _______________________________________________ mailop mailing list [email protected] https://list.mailop.org/listinfo/mailop
