Notice: Known Issue with Emails Used for Account Sign-Ups on this Discourse

For some time now, we’ve had reports behind the scenes about users being unable to create accounts when using free email providers such as Microsoft Outlook’s free addresses, Hotmail and MSN (same Microsoft provider), Yahoo, Google Mail (GMail), and other free email providers.

A large portion of the provider for the VPS infrastructure that powers this site’s SMTP are blacklisted as ‘abused’ by Microsoft and other providers. This is likely because VPS providers and “hosting” providers tend to get blacklisted hard for abusive use, etc.

It was not until very recently (July 2023) that Microsoft and these other providers have started actually bouncing messages back with error traces, rather than silently ‘accepting’ and dropping these messages (which prevented us from diagnosing this issue).

For now, if you are using Microsoft accounts and email (, MSN, Hotmail, any Microsoft 365 tenants, etc.), you will not be able to sign up properly to this Discourse site with that address.

We are working with our VPS provider for the SMTP server to get our IPs whitelisted and will update this notice in the future.

We apologize for this inconvenience, but the changes that gave us debugging data was not available prior to recently, so we had been ‘radio silent’ on the issue because we didn’t have any useful info on this.


We are in the process of migrating SMTP servers for this Discourse instance.

For now, messages from the new SMTP server deliver but end up in “junk” on Microsoft tenants and Microsoft-owned addresses. We are working to improve this however it will take time.

As of now, you might be able to register with these ‘free’ addresses like Outlook, Hotmail, etc. but we cannot guarantee this will last indefinitely for delivery.


We have migrated SMTP servers, however the IP ranges have still been blocked.

I am working with the ISP to unblock the ranges, which are at a far deeper block level than I can unlist at Microsoft.

Therefore, you will still be unable to register if you are using free mail providers at this time. We are still working on this issue.


If I may…

I’ve had to deal with similar. One, there are certain domain names that will almost never make it through their filters. I do not believe .me is on that list.

But, if you can send a test email:

That’s the site I used to diagnose the problems and get things squared away. My emails now make it through the junk mail filters and even end up properly in the inbox.

You send a test email to the address they give you. You wait a few seconds. You then can click the button to get your results. It needs to be close to perfect to make it all the way into an inbox.


We know the core issue - this mail tester system won’t help us in these cases. The core issue is MS and other providers blacklist by IP. We know this from the Bounces we’re seeing. Mail isn’t misconfigured, MS and others simply block the IPs. It’s not by domain in this case.

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