Description:

Address type is incorrect (possibly misspelled)

Luckily, this response is extremely straight forward. The suggestion event states, "Possibly misspelled."

• Check for email address misspelling(s).
• Ensure that the email address still exists.

SMTP error 501 5.1.3 Invalid address

SMTP error 553 5.1.3 User address required !

SMTP error 501 5.1.3 Bad recipient address syntax

# 501 # 510 # 553