smtp error (451) failed to add recipient [email protected]

[guntoro]

hai guys....
i have some problem with my webmail. if i send email, roundcube always show info like this

"SMTP error (451) failed to add recipient [email protected]"

may I ask for solutions from you guys, for solving problem I faced.

thanks.

[JohnDoh]

451: Requested action aborted: local error in processing

check you smtp server logs, do you need to configure smtp auth?