In the Discourse instance I help run, I’ve gotten a number of “Unknown To: Address” error reports recently… I’ve gotten it myself and have gotten a number of reports from users. In my case, I was replying to a PM. Other cases were people replying to a topic by email and their messages getting reje…

Well, it’d be handy to know where these errors are being seen (preferably with screenshots), along with a description of how your system is setup, exactly.

Good point! We use the standard reply-by-email settings: [Discuss-2] But when I replied to a recent PM, I got an error from that reply-by-email address: [Discuss-1] We run it on DigitalOcean use SendGrid for email, and have an incoming email address set up on our Google Apps suite. (I’m not …

For that bounce, there should be something in Emails → Rejected. If there isn’t, you’ve got yourself a mystery. I’d start by looking in the Rails logs for the original e-mail, and comparing it against the message that was sent, to see if something along the way is mangling the e-mail.

Yeah, there’s definitely nothing in Emails → Rejected. I’ll follow those steps you recommend to dig into it, though. Thanks!

@jedc768 , I’ve had the same issues with failed Reply by Email emails since upgrading to Discourse v2.0.0.beta1 +4. I’ve seen rejected emails with “Email issue – Unknown To: Address” and " “Email issue – User Not Found”. I even had @nixie investigate with me and we came up empty on a root cause. I c…

We haven’t yet - I haven’t noticed any of these errors in Emails → Rejected, so it’s only if people manually forward them to me that I hear about them. We’re currently on v2.0.0.beta1 +7 and it does sound like we’re encountering the same phenomenon. The engineers I work with are going to dig into …

As far as I’m aware, we haven’t had any queries from any of our hosted customers about problems like this, so the problem is less likely to be in Discourse proper, and more in how you’re getting email into Discourse. If you’re both using gmail/gapps via POP, perhaps they’re doing something funky?

That’s good information - thanks, Matt. We haven’t changed our settings in ages - still using pop.gmail.com with SSL on port 995. Any chance there’s a new best practice for this? I’m wondering if it’s still just @JoelZaslofsky and me having problems with this, or if others are seeing this, too? …

That explains it! We set up all our infrastructure about a year before that guide came out. :slight_smile: Thanks for the link.

Started getting 'Unknown To: Address" failures

Support

mpalmer (Matt Palmer) February 7, 2018, 12:38am 10

Indeed. We haven’t used POP3 polling on hosted sites for… well, since about three months before this guide was written.

Topic		Replies	Views
Confused by Error Message From Reply-by-Email Support	26	3151	June 4, 2020
Troubleshoot reply by email Self-Hosting email , how-to	0	26857	April 4, 2016
Spam with from address set to reply by email address Support	4	679	May 23, 2018
Wrong rejection email is being sent Bug	9	3542	October 15, 2017
Reply by email Issues Support	4	856	September 1, 2021

Started getting 'Unknown To: Address" failures

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