As answered on https://github.com/FusionAuth/fusionauth-issues/issues/1263, this was indeed an issue with port 25.

For anybody encountering the same problem:

1. Try switching to another port (587, 465, or 2525)
2. Try switching TLS to SSL and the other way around with all the different port configurations.

Took me a while to find this, probably because I mistyped 587 as 578.

Hi,

It's fairly easy to generate an API key for the FusionAuth APIs, which is great. However I now also want to protect my application outside of the user context for application<>application communication.

Is there an obvious way I'm missing to achieve this with the current functions offered by FusionAuth?

• I could create a service user with oAuth validation and refreshing the tokens, which is fairly heavy for the use case
• I could just work outside of FusionAuth and semi-hardcode API keys in the API to check the validity

Let me know, thanks!

As answered on https://github.com/FusionAuth/fusionauth-issues/issues/1263, this was indeed an issue with port 25.

For anybody encountering the same problem:

1. Try switching to another port (587, 465, or 2525)
2. Try switching TLS to SSL and the other way around with all the different port configurations.

Took me a while to find this, probably because I mistyped 587 as 578.

I'm having exactly the same with Mailgun. It looks like a bug, we have tried everything. I have now reported it here: https://fusionauth.io/community/forum/topic/1075/amazon-ses-issues-as-smtp-with-fusionauth

We have this on a FusionAuth cloud deployment as deployed by FusionAuth themselves.