###If you are following the local docker image setup:
- Your ISP may be blocking port 25.
- The mail may be getting stuck in a spam filter because of the localhost domain.
To get around this you can go to the settings menu in the top left (the three dots) and select “Get Team Invite Link”. You can then manually send this link to allow people to signup.
###If you are following the AWS Elastic Beanstalk setup:
- Make sure you mapped the domain properly
- Make sure you have set the MATTERMOST_DOMAIN environment variable.