Mail send error after changing email address

[w1z8it]

I finally sorted out all issues, postfix is working great I can send emails from telnet no problem through my ISP's SMTP server, and it was working on the forums... however the emails were using my personal email address by default which is unsatisfactory, so I changed it in Admin::Configuration::Server Settings::General, but since then it's been giving me the following error log each time an email should be sent:

Ran into problems sending Mail. Error: 502 Error: command not implemented

I even changed my email address back to my personal email but it's somehow still not working, what gives?

[w1z8it]

Disregard I solved it myself.

The problem was SMTP server, I changed it to localhost and it works