Requirements for SMTP check

[sfarkas1988]

Hey, what are the server requirements to get smtp: { valid: true }?
I know on aws the outbound port 25 is not allowed.
Locally in Java I get a successful smtp check but with your tool, I always get smtp: { valid: false }

[souravprogrammer]

@sfarkas1988 Hi , could you please specify the issue more , at which server its giving SMTP false every time

[sfarkas1988]

I do have a list of private email lists I can't share.
But the point is, I never get a successful smtp = true response.
Which might be the reason that the smtp check itself does not always work on all environments.
There should be some requirements for the server where I run the command like proper DNS setup so the responding SMTP server would accept the request. This is how I understand the whole SMTP thing.