Hi,
my store encounter email issue after upgrade to 4.5.1
my order notification email fail to sent to customer, but successfully sent to order department and vendor. only send notify email to customer having issue, prompt out error
ErrorMessage could not be sent.
Mailer Error: SMTP Error: data not accepted.SMTP server error: DATA END command failed Detail: Relaying disallowed as Stark Industries SMTP code: 553
anyone please help me, im have no clue what happen to my store, send notify to order department and vendor successful without error, only send to customer having error even my customer email is valid.
i try install clean version 4.5.1, still having the same issue.
Thank You