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Introducing Simon 5!

Simon version 5 is now available. It is a massive update, introducing a much-requested feature: syncing the Simon data between multiple Macs, plus a Simon Status service, a Link Checker filter, improved Find filter, iMessage and Speak Error notifiers, a new app icon, and much more.

Important: please note that Simon 5 requires a minimum of macOS 10.12 (Sierra), and is a paid upgrade from Simon 4. Purchasers since September 1, 2020 automatically get a version 5 license (that also works in previous versions).

Read the Simon What's New page for details.

Mail not working migrating to new server

After migrating Simon to a new mac mini running Mavericks, we are unable to send email alerts. We can send mail from Postfix itself, but Simon throws off an error:

Simon: No mail servers for domain ""

Any help would be appreciated!

David Sinclair's picture

Re: Mail not working migrating to new server

You're using a Sendmail transport? I don't know whether or not any configuration is needed for that. For the Apple Mail transport, you'd need to set up accounts in Apple Mail.

Re: Mail not working migrating to new server

I'm not at the point to test Simon's e-mail plug-in as I've still taking care of the underlying plumbing before I make a purchase and do so.

I did configure Postfix, which is supplied by Apple and is a fine MTA that accepts all sendmail commands, as a smtp relay to my Gmail account using the great guidance found at

It worked as documented via the command line and now will have to do a little script that I can get Simon to use.

I'm going to this trouble because my Mac Mini running 10.8.5 is just a headless server and I try to keep the number of running apps on it to a minimum.

David Sinclair's picture

Re: Mail not working migrating to new server

Sorry, your comment was held up for moderation, since it included a link.

I'm afraid I'm not really sufficiently familiar with sendmail to help diagnose issues with it. It's external to Simon. Can anyone else help?

I will actually probably remove Sendmail as a transport option in a future release, since it isn't supported by more modern mail frameworks. It may be possible to continue supporting it via a custom script, though.