Hi Chris, Regardless of what email provider you use, having a lot of email bounces is likely to affect the reputation of your sending domain. Even if you own the email domain, recipients' domains may mark your messages as spam or quarantine them on the basis of that reputation. You will need to improve the quality of your data. Depending on the proportion of addresses that are incorrect, you might consider turning off email notifications until you can correct the data.
Are there particular reasons for choosing the configuration of Postfix over Koha's built-in SMTP server settings? There is additional administrative overhead to setting up Postfix—and those settings will not be included in Koha's regular backup routine. The SMTP server settings, on the other hand, are backed up with the rest of the database. SPF, DKIM, and DMARC will not be configured in Koha, but rather at your DNS host, which may or may not be your domain host. Your DNS/domain host may have published guides for setting up these functions, so it should be your first point of reference. If you're not sure where you need to start, I encourage you to share more details about your environment—without exposing operational details that could be exploited. Regards, David Liddle Koha System Administrator & Email Administrator Seminar für Sprache und Kultur, https://spracheundkultur.org On Tue, Dec 30, 2025 at 3:51 PM Chris Brown <[email protected]> wrote: > Hello, > > First, best wishes to all for the new year. > > I manage a koha system that supports 7 volunteer-run libraries in > Sheffield, UK. Since 2018 we have used gmail as a relay for sending overdue > notifications etc. Recently, Google informed me that they have disabled the > service due to violation of their terms of service. We are not sure exactly > what they are unhappy about but we suspect it might be due to a high > proportion of bounced messages, (We have rather too many incorrect email > addresses in koha.) > > I would be interested to hear from anyone who has had a similar problem, > and has found a solution. In particular, I would like some guidance on > setting up Postfix to send out email directly (without using gmail as a > relay), and setting up SPF, DKIM and DMARC. In case it is relevant, we are > using koha 22.11. > > Thanks and Best Regards, > > Chris Brown > _______________________________________________ > > Koha mailing list http://koha-community.org > [email protected] > Unsubscribe: https://lists.katipo.co.nz/mailman/listinfo/koha > _______________________________________________ Koha mailing list http://koha-community.org [email protected] Unsubscribe: https://lists.katipo.co.nz/mailman/listinfo/koha
