postfix - smtp relay setting in

I have Sendinblue as a smtp mail relay server and I get this error when I send a mail out----

Diagnostic-Code: smtp; 530 Error: authentication Required —

What could be the problem?

And this is what I added in postfix
smtp_sasl_password_maps = static:myblahusername:myblahpassword
smtp_sasl_security_options = noanonymous
smtp_tls_security_level = may
header_size_limit = 4096000
relayhost =

Did you enable SMTP auth

smtp_sasl_auth_enable = yes

Yes, I did. I am sorry I forgot to mention.

Actually this is enabled:
smtpd_sasl_auth_enable = yes

And it started working by simply removing a “d” from smtpd_sasl_auth_enable = yes.

And I also did “yum install cyrus-sasl cyrus-sasl-lib cyrus-sasl-plain.”

Glad it worked out for you, sendinblue documentation is quite limited for now.